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UNIVERSITY   OF    CALIFORNIA    PUBLICATIONS.        „rtl ,  f^il   ,  ^  ^.f 

— — -— ~ ~ ~~~"^ — ^— ^        CJLL-O-  It  AbrtioUL 


COLLEGE  OF  AGRICULTURE. 


AGRICULTURAL  EXPERIMENT  STATION. 

E.  W.  HILGARD Director. 

E.  J.  WICKSON      ...        .      Acting  Director. 


NATURE,  VALUE,  AND  UTILIZATION 
OF  ALKALI  LANDS, 


AND 


TOLERANCE  OF  ALKALI  BY  CULTURES. 


By  E.  W.  HILGARD  and  R.  H.  LOUGHRIDGE. 


REVISED  REPRINT  OF  BULLETINS  Nos.  128  AND  133. 

(December,  1905.) 


SACRAMENTO: 
w.  w.  shannon,    :    :    :    :     :    superintendent  state  printing. 

1906. 


BENJAMIN  IDE  WHEELER,  Ph.D.,  LL.D.,  President  of  the  University. 

EXPERIMENT  STATION  STAFF  (JANUARY,   1906). 

E.  W.  HTLGARD,  Ph.D.,  LL.D.,  Director  and  Chemist.     (Absent  on  leave.) 

E.J.  WICKSON,  M.A.,  Acting  Director  and  Horticulturist. 

W.  A.  SETCHELL,  Ph.D.,  Botanist. 

EIvWOOD  MEAD,  M.S.,  C.E  ,  Irrigation  Engineer. 

C.  W.  WOODWORTH,  M.S.,  Entomologist. 

R.  H.  LOUGHRIDGE,  Ph.D.,  Agricultural  Geologist  and  Soil  Physicist.     (Soils  and  Alkali.) 

M.  E.  JAFFA,  M.S.,  Assistant  Chemist.     (Eoods,  Nutrition.) 

G.  W.  SHAW,  M.A.,  Ph.D.,  Assistant  Chemist.     (Starches,  Oils,  Beet-Sugar.) 

GEORGE  E   COLBY,  M.S.,  Assistant  Chemist.     {Fruits,  Waters,  Insecticides.) 

RALPH  E.  SMITH,  B.S.,  Plant  Pathologist. 

A.  R.  WARD,  B.S.A.,  D.V.M.,  Veterinarian  and  Bacteriologist. 

E.  W.  MAJOR,  B.Agr.,  Animal  Industry. 

E.  H.  TWIGHT,  B.'Sc,  Diplome  E.A.M.,  Viticulturist. 

F.  T.  BIOLETTI,  M.S.,  Viticulturist. 

WARREN  T.  CLARKE,  B.S..  Assistant  Entomologist  and  Asst.  Supt.  Farmers'  Institutes. 

H.  M.  HALL,  M.S  ,  Assistant  Botanist. 

GEORGE  ROBERTS,  M.S.,  Assistant  Chemist,  in  charge  of  Fertilizer  Control. 

C    M.  HARING,  D.V.  M.,  Assistant  Veterinarian  and  Bacteriologist. 

ALBERT  M.  WEST,  B.S.,  Assistant  Plant  Pathologist. 

E.  H.  SMITH,  M.S.,  Assistant  Plant  Pathologist. 

G.  R.  STEWART,  Student  Assistant  in  Station  Laboratory. 
D.  L.  BUNNELL,  Clerk  to  the  Director. 


R.  E.  MANSELL,  Foreman  of  Central  Station  Grounds. 

JOHN  TUOHY,  Patron,     ) 

V   Tulare  Substation,  Tulare. 
J.  FORRER,  Foreman,        ) 

J.  W.  MILLS,  Pomona,  in  charge  Cooperation  Experiments  in  Southern  California. 

J.  W.  ROPER,  Patron,  ) 

V    University  Forestry  Station,  Chico. 


HENRY  WIGHTMAN,  In  charge, 

ROY  JONES,  Patron,  ) 

]-    University  Forestry  Station,  Santa  Monica. 
J.   H.   BARBER,   Foreman,  ) 

VINCENT  J.  HUNTLEY,  Foreman  of  California  Poultry  Experiment  Station,  Petaluma. 


The  Station  publications  (Reports  and  Bulletins),  so  long  as  avail- 
able, will  be  sent  to  any  citizen  of  the  State  on  application. 


TABLE    OF    CONTENTS. 


Page. 

OCCURRENCE  AND  CHARACTERISTICS  OF  ALKALI  LANDS 5 

How  plants  are  injured  by  alkali ;  Effects  of  irrigation 7 

Distribution  of  the  alkali  salts 8 

Composition  of  the  salts  ;  Summary  of  conclusions 13 

UTILIZATION  AND  RECLAMATION  OF  ALKALI  LANDS 16 

Counteracting  evaporation;   Diluting  the  salts;    Chemical  remedies;   Stable 

manure  and  other  fertilizers 1 16 

Removing  the  salts  from  the  soil ..  .  21 

Will  it  pay  to  reclaim  alkali  lands? 22 

Crops  suitable  for  alkali  lands 24 

TOLERANCE  OF  ALKALI  SALTS  BY  VARIOUS  CULTURES 28 

Field  of  observation ;  Extent  of  investigation ;  Difficulties  in  interpretation  of 

results 28 

Grain:  Wheat,  Barley,  Rye 31 

Legumes  and  Fodder  Plants:  Alfalfa,.  Blue  European  Lupin,  Hairy  Vetch, 

Bur  Clover,  Fenugreek,  Crimson  Clover,  Australian  Saltbush,  Sorghum..      '  34 
Root  Crops  and  Vegetables:  Sugar  Beets,  Carrots,  Potatoes,  Onions,  Celery, 

Spinach,  Broad  Bean 38 

Grasses,  Textile  Plants,  and  Weeds .._ 41 

Grapevines:  Effect  of  alkali  upon  the  composition  of  grapes 42 

Orchard  Crops:  Almonds,  Apples,  Apricots,  Figs,  Lemons,  Oranges,  Peaches, 

Pears,  Plums,  Prunes,  Walnuts 45 

Timber  and  Shade  Trees:  Eucalypts,  Acacias,  Palms,  Sycamores,  etc. 53 

General  Summary,  showing  tolerances  of  crops 55 

IRRIGATION  WITH  SALINE  WATERS 56 

Limits  of  saline  contents 60 

RECLAIMABLE    AND    IRRECLAIMABLE    ALKALI    LANDS    AS    DISTIN- 
GUISHED BY  THEIR  NATURAL  VEGETATION 61 

Tussock  Grass;  Greasewood;  Dwarf  Samphire;  Bushy  Samphire;  Saltwort; 

Alkali  Heath  ;  Cressa 63 

Relative  tolerance  of  different  species,  table  showing  optimum,  maximum, 

and  minimum  of  salts  tolerated  by  alkali  plants 69 

Total  salt  indicators;  Salsoda  indicators;  Neutral  salt  indicators 70 

CONCLUSIONS 71 


NATURE,  VALUE,  AND  UTILIZATION  OF 
ALKALI  LANDS, 

AND 

THE  TOLERANCE  OF  CROPS  FOR  ALKALL 


By  E.  W.  HILGARD  and  R.  H.  LOUGHRIDGE. 


[The  continuous  and  pressing  demand  for  information  on  alkali  lands  and  their 
utilization  having  exhausted  the  printed  matter  heretofore  published  by  this  Station 
on  the  subject,  it  seems  best  to  publish  a  general  summary  of  the  results  of  our 
investigations,  made  during  the  past  twenty  years,  for  the  use  of  farmers  and  land 
owners  and  the  general  public.  Those  desiring  more  detailed  information  will  find  the 
record,  so  far  as  printed,  in  the  reports  of  the  Station  from  1879  to  1898,  of  which 
those  from  1898  to  1904  are  still  available  for  distribution.] 

OCCURRENCE   AND    CHARACTERISTICS    OF    ALKALI    SOILS. 

Alkali  lands  must  be  pointedly  distinguished  from  the  salty  lands  of 
sea  margins  or  marshes,  from  which  they  differ  in  both  their  origin 
and  essential  nature.  Marsh  lands  derive  their  salts  from  sea  water 
that  occasionally  overflows  them,  and  the  salts  which  impregnate  them 
are  essentially  ' '  sea  salts ' ' ;  that  is,  common  salt,  together  w^th  bittern, 
epsom  salt,  etc.  Very  little  of  what  would  be  useful  to  vegetation  or 
desirable  as  a  fertilizer  is  contained  in  the  salts  impregnating  such 
soils;  and  they  are  by  no  means  always  intrinsically  rich  in  plant- 
food,  but  vary  greatly  in  this  respect. 

Alkali  lands  bear  no  definite  relation  to  the  sea;  they  are  mostly 
remote  from  it  or  from  any  former  sea  bed,  so  that  they  have  sometimes 
been  designated  as  "terrestrial  salt  lands."  Their  existence  is  usually 
definitely  traceable  to  climatic  conditions  alone.  They  are  the  natural 
result  of  a  light  rainfall,  insufficient  to  leach  out  of  the  land  the  salts 
that  always  form  in  it  by  the  progressive  weathering  of  the  rock 
powder  of  which  all  soils  largely"  consist.  Where  the  rainfall  is 
abundant,  that  portion  of  the  salts  corresponding  to  "sea  salts"  is 
leached  out  into  the  bottom  water,  and  with  this  passes  through 
springs  and  rivulets  into  the  country  drainage,  to  be  finally  carried  to 
the  ocean.  Another  portion  of  the  salts  formed  by  weathering,  how- 
ever, is  partially  or  wholly  retained  by  the  soil ;  it  is  that  portion  chiefly 
useful  as  plant-food. 

It  follows  that  when,  in  consequence  of  insufficient  rainfall,  all  or 
most  of  the  salts  are  retained  in  the  soil,  they  will  contain  not  only 


t>  UNIVERSITY    OF    CALIFORNIA— EXPERIMENT   STATION. 

the  ingredients  of  sea  water,  but  also  those  useful  to  plants.  In  rainy 
climates  a  large  portion  even  of  the  latter  is  leached  out  and  carried 
away.  In  extremely  arid  climates  their  entire  mass  remains  in  the 
soils;  and,  being  largely  soluble  in  water,  evaporation  during  the  dry' 
season  brings  them  to  the  surface,  where  they  may  accumulate  to  such 
an  extent  as  to  render  the  growth  of  ordinary  useful  vegetation  im- 
possible; as  is  seen  in  "alkali  spots,"  and  sometimes  in  extensive  tracts 
of  "alkali  desert." 

In  looking  over  a  rainfall  map  of  the  globe  we  see  that  a  very  consid- 
erable portion  of  the  earth's  surface  has  deficient  rainfall,  the  latter 
term  being  commonly  meant  to  imply  any  annual  average  less  than  20 
inches  (500  millimeters).  Zones  of  deficient  rainfall  intervene  between 
the  tropics  and  the  temperate  humid  zones  on  both  the  northern  and 
southern  hemispheres,  their  width  ranging  respectively  from  30  to  12 
degrees,  or  from  2,000  to  800  miles.  The  arid  region  thus  defined 
includes,  in  North  America,  most  of  the  country  lying  west  of  the  one 
hundredth  meridian  up  to  the  Cascade  mountains,  and  northward 
beyond  the  line  of  the  United  States;  southward,  it  reaches  far  into 
Mexico,  including  especially  the  Mexican  plateau.  In  South  America 
it  includes  nearly  all  the  Pacific  slope  (Peru  and  Chile)  south  to 
Araucania ;  and  eastward  of  the  Andes,  the  greater  portion  of  the 
plains  of  western  Brazil  and  Argentina.  In  Europe  only  a  very  small 
portion  of  the  Mediterranean  border  is  included ;  but  the  entire  African 
coast  belt  opposite,  with  the  Saharan  and  Libyan  deserts,  Egypt  and 
Arabia  are  included  therein,  as  well  as  a  considerable  portion  of  South 
Africa.  $  Asia,  Asia  Minor,  Syria  (with  Palestine),  Mesopotamia, 
Persia,  and  northwestern  India  up  to  the  Ganges,  and  northward,  the 
great  plains  or  steppes  of  central  Asia  eastward  to  Mongolia  and  western 
China,  fall  into  the  same  category;  as  does  also  a  large  portion  of  the 
Australian  continent. 

Over  these  vast  areas  alkali  lands  occur  to  a  greater  or  less  extent, 
the  exceptions  being  the  mountain  regions  and  adjacent  lands  on  the 
side  exposed  to  prevailing  oceanic  winds.  It  will  therefore  be  seen  that 
the  problem  of  the  utilization  of  alkali  lands  for  agriculture  is  not  of 
local  interest  only,  but  is  of  world-wide  importance.  It  will  also  be 
noted  that  many  of  the  countries  referred  to  are  those  in  which  the 
most  ancient  civilizations  have  existed  in  the  past,  but  which  at  present, 
with  few  exceptions,  are  occupied  by  semicivilized  people  only.  It  is 
doubtless  from  this  cause  that  the  nature  of  alkali  lands  has  until  now 
been  so  little  understood  that  even  their  essential  distinctness  from  the 
sea-border  lands  has  been  but  lately  recognized  in  full.  Moreover,  the 
great  intrinsic  fertility  of  these  lands  has  been  very  little  appreciated, 
their  repellent  aspect  causing  them  to  be  generally  considered  as  waste 
lands. 


INJURY   TO   PLANTS   BY   ALKALI.  7 

This  aspect  is  essentially  due  to  their  natural  vegetation  being  in 
most  cases  confined  to  plants  useless  to  man,  commonly  designated  as 
"saline  vegetation,"  of  which  but  little  is  usually  relished  by  cattle. 
Exceptions  to  this  rule  occur  in  America,  Australia,  and  Africa,  where 
the  "saltbushes"  of  the  former  two,  and  the  "karroo"  vegetation  of 
the  letter,  form  valuable  pasture  grounds.  Apart  from  these,  however, 
the  efforts  to  find  for  these  lands,  while  in  their  natural  condition, 
culture  plants  generally  acceptable,  or  at  least  profitable,  outside  of 
forage  crops,  have  not  been  very  successful. 

HOW  PLANTS  ARE  INJURED  BY  ALKALI. 

When  we  examine  plants  that  have  been  injured  by  alkali,  we  will 
usually  find  that  the  damage  has  been  done  near  the  base  of  the  trunk, 
or  root  crown;  rarely  at  any  considerable  depth  in  the  soil  itself.  In 
the  case  of  green  herbaceous  stems,  the  bark  is  found  to  have  turned  to 
a  brownish  tinge  for  half  an  inch  or  more,  so  as  to  be  soft  and  easily 
peeled  off.  In  the  case  of  trees,  the  rough  bark  is  found  to  be  of  a 
dark,  almost  black,  tint,  and  the  green  layer  underneath  has,  as  in  the 
<?ase  of  an  herbaceous  stem,  been  turned  brown  to  a  greater  or  less 
extent.  In  either  case  the  plant  has  been  practically  '"girdled,"  the 
effect  being  aggravated  by  the  diseased  sap  poisoning,  more  or  less,  the 
whole  stem  and  roots.  The  plant  may  not  die,  but  it  will  be  quite 
certain  to  become  unprofitable  to  the  grower. 

It  is  mainly  in  the  case  of  land  very  heavily  charged  with  common 
salt,  as  in  the  marshes  bordering  the  sea  or  salt  lakes,  that  injury  arises 
irom  the  direct  effects  of  the  salty  soil-water  upon  the  feeding  roots 
themselves.  In  a  few  cases  the  gradual  rise  of  salt  water  from  below, 
in  consequence  of  defective  drainage,  has  seriously  injured,  and  even 
destroyed,  old  orange  orchards. 

The  fact  that  in  cultivated  land  the  injury  is  usually  found  to  occur 
near  the  surface  of  the  soil,  concurrently  with  the  well-known  fact  that 
the  maximum  accumulation  of  salts  at  the  surface  is  always  found  near 
the  end  of  the  dry  season,  indicates  clearly  that  this  accumulation  is 
due  to  evaporation  at  the  surface.  The  latter  is  often  found  covered 
with  a  crust  consisting  of  earth  cemented  by  the  crystallized  salts,  and 
later  in  the  season  with  a  layer  of  whitish  dust  resulting  from  the 
drying-out  of  the  crust  first  formed.  It  is  this  dust  which  becomes  so 
annoying  to  the  inhabitants  and  travelers  in  alkali  regions,  when  high 
winds  prevail,  irritating  the  eyes  and  nostrils  and  parching  the  lips. 

EFFECTS   OF   IRRIGATION. 

One  of  the  most  annoying  and  discouraging  features  of  the  cultiva- 
tion of  lands  in  alkali  regions  is  that,  although  in  their  natural  condition 
they  may  show  but  little  alkail  on  their  surface,  and  that  mostly  in 


8  UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 

limited  spots,  usually  somewhat  depressed  below  the  general  surface, 
these  spots  are  found  to  enlarge  rapidly  as  irrigation  is  practiced ;  and 
since  alkali  salts  are  the  symptoms  and  result  of  insufficient  rainfall, 
irrigation  is  a  necessary  condition  of  agriculture  wherever  they  pre- 
vail. Under  irrigation,  neighboring  spots  will  oftentimes  merge  together 
into  one  large  one,  and  at  times  the  entire  area,  once  highly  productive 
and  perhaps  covered  with  valuable  plantations  of  trees  or  vines,  will 
become  incapable  of  supporting  useful  growth.  This  annoying 
phenomenon  is  popularly  known  as  "the  rise  of  the  alkali"  in  the 
western  United  States,  but  is  equally  well  known  in  India  and  other 
irrigation  regions. 

The  process  by  which  the  salts  rise  to  the  surface  is  the  same  as  that 
by  which  oil  rises  in  a  wick.  The  soil  being  impregnated  with  a  solution 
of  the  alkali  salts,  and  acting  like  the  wick,  the  salts  naturally  remain 
behind  on  the  surface  as  the  water  evaporates,  the  process  only  stopping 
when  the  moisture  in  the  soil  is  exhausted.  We  thus  not  infrequently 
find  that  after  an  unusually  heavy  rainfall  there  follows  a  heavier 
accumulation  of  alkali  salts  at  the  surface,  while  a  light  shower  pro- 
duces no  perceptible  permanent  effect,  We  are  thus  taught  that,  within 
certain  limits,  the  more  water  evaporates  during  the  season  the  heavier 
will  be  the  rise  of  the  alkali;  provided  that  the  water  is  not  so  abundant 
as  to  leach  the  salts  through  the  soil  and  subsoil  into  the  subdrainage. 

Worst  of  all,  however,  is  the  effect  of  irrigation  ditches  laid  in  sandy 
lands  (such  as  are  naturally  predominant  in  arid  regions),  without 
proper  provision  against  seepage.  The  ditch  water  then  gradually  fills 
up  the  entire  substrata  so  far  as  they  are  permeable,  and  the  water-table 
rises  from  below  until  it  reaches  nearly  to  the  ditch  level;  shallowing 
the  subsoil,  drowning  out  the  deep  roots  of  all  vegetation,  and  bringing 
close  to  the  surface  the  entire  mass  of  alkali  salts  previously  diffused 
through  many  feet  of  substrata.  If  this  condition  is  allowed  to  con- 
tinue for  some  time,  alkali  salts  originally  "white"  will  by  a  chemical 
change  become  ' '  black ' '  by  the  formation  of  carbonate  of  soda  from  the 
glauber  and  common  salts ;  greatly  aggravating  the  injury  to  vegetation. 
More  than  this,  if  such  swamping  is  allowed  to  continue  for  a  number 
of  years,  the  land  may  be  permanently  injured ;  so  that  even  after  the 
alkali  is  removed,  the  soil  remains  inert  and  unthrifty  for  years. 

DETERMINATION  OF  THE  DISTRIBUTION  OF  THE  ALKALI  SALTS. 

In  order  to  gain  a  basis  for  the  possible  means  of  reclaiming  alkali 
lands,  it  is  evidently  necessary  to  determine  by  direct  observation  the 
manner  in  which  the  salts  are  distributed  in  the  soils  under  different 
conditions.  This  can  be  done  by  sampling  the  soil  at  short  intervals  of 
depth,  and  leaching  out  and  analyzing  each  sample  separately.    While 


DISTRIBUTION  OF  ALKALI   SALTS. 


this  involves  a  great  deal  of 
work,  it  is  manifestly  the  only 
conclusive  method. 

A  series  of  such  investiga- 
tions has  been  first  carried  out 
by  the  California  Experiment 
Station  during  the  years  1894 
and  1895,  with  samples  taken 
in  or  near  the  substations  near 
Tulare  and  Chino,  CaL,  with 
the  results  as  given  below.  It 
should  be  understood  that  the 
alkali  in  the  Tulare  region  is 
naturally  mostly  of  the  "black" 
kind,  that  is,  consisting  largely 
of  carbonate  of  soda,  which  dis- 
solves the  humus  of  the  soil  and 
thus  gives  rise  to  dark-colored 
spots  and  inky  water-puddles. 
The  soil  is  a  rather  sandy,  gray 
loam  (see  Report  California  Ex- 
periment Station,  1889).  On 
the  Chino  tract,  on  the  contrary, 
the  soil  is  a  close-grained,  rather 
heavy  loam,  naturally  subirri- 
gated;  the  salts  are  likewise 
largely  "black,"  the  sodium 
carbonate  being  about  one  third 
of  the  whole. 

Fig.  1  represents  the  condi- 
tion of  the  salts  in  an  "alkali 
spot ' '  as  found  at  the  end  of  the 
dry  season  at  the  Tulare  substa- 
tion. The  soil  was  sampled  to 
the  depth  of  two  feet,  at  inter- 
vals of  three  inches  each.  The 
depths  are  entered  in  the  verti- 
cal line  to  the  left ;  the  percent- 
ages of  the  total  salts  and  of 
each  of  the  principal  ingredi- 
ents ar  entered  in  decimal  frac- 
tions of  one  per  cent  on 
horizontal  lines  running  to  the 
right,   as  indicated   on  the  top 


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DISTRIBUTION   OF  ALKALI   SALTS.  11 

line  of  the  plate.  Broken  lines  connecting  the  data  in  each  case  facili- 
tate the  understanding  of  the  results.  It  is  thus  easy  to  see  that  at  this 
time  almost  the  entire  mass  of  the  salts  was  accumulated  within  the 
first  six  inches  from  the  surface,  while  lower  down  the  soil  contained 
so  little  that  few  culture  plants  would  be  hurt  by  them. 

Fig.  2  represents  similarly  the  state  of  things  in  a  natural  soil  along- 
side of  the  alkali  spot,  but  in  which  the  native  vegetation  of  brilliant 
flowers  develops  annually  without  any  hindrance  from  alkali.  Samples 
were  taken  from  this  spot  in  March,  near  the  end  of  the  wet,  and  in 
September,  near  the  end  of  the  dry,  season,  and  each  series  fully 
analyzed.  There  was  scarcely  a  noticeable  difference  in  the  results 
obtained.  It  is  seen  in  the  figure  that  down  to  the  depth  of  fifteen 
inches  there  was  practically  no  alkali  found  (0.035  per  cent),  and  it 
was  within  these  iifteen  inches  of  soil  that  the  native  plants  mostly  had 
their  roots  and  developed  their  annual  growth.  But  from  that  level 
downward  the  alkali  rapidly  increased,  and  reached  a  maximum  (0.529 
per  cent)  at  about  thirty-three  inches,  decreasing  rapidly  thence  until, 
at  the  end  of  the  fourth  foot  in  depth,  there  was  no  more  alkali  than 
within  the  first  foot  from  the  surface.  In  other  words,  the  bulk  of  the 
raits  had  accumulated  at  the  greatest  depth  to  which  the  annual  rainfall 
(7  inches)  ever  reaches,  forming  there  a  sheet  of  tough,  intractable  clay 
hardpan.  The  shallow-rooted  native  plants  germinated  their  seeds 
freely  on  the  alkali-free  surface,  their  roots  kept  above  the  strongly 
charged  subsoil,  and  through  them  and  the  stems  and  foliage  all  the 
soil  moisture  was  evaporated  by  the  time  the  plants  died.  Thus  no 
alkali  was  brought  up  from  below  by  evaporation.  The  seeds  shed  would 
remain  uninjured,  and  would  again  germinate  the  coming  season. 

It  is  thus  that  the  luxuriant  vegetation  of  the  San  Joaquin  plains, 
dotted  with  occasional  alkali  spots,  is  maintained,  the  spots  them- 
selves being  almost  always  depressions  in  which  the  rain  water  may 
gather,  and  where,  in  consequence  of  the  increased  evaporation,  the 
noxious  salts  have  risen  to  the  surface  and  render  impossible  all  but 
the  most  resistant  saline  growth ;  particularly  when,  in  consequence  of 
maceration  and  fermentation  in  the  soil,  the  formation  of  carbonate  of 
soda  (black  alkali)  has  caused  the  surface  to  sink  and  become  almost 
water-tight. 

After  several  years'  cultivation  with  irrigation  on  the  same  land  as 
in  the  last  figure,  a  crop  of  barley  four  feet  high  was  grown  on  the  land. 
Investigation  proved  that  here  the  condition  of  the  soil  was  intermediate 
between  the  two  preceding  figures.  The  irrigation  water  had  dissolved 
the  alkali  of  the  subsoil,  and  the  abundant  evaporation  had  brought  it 
nearer  the  surface ;  but  the  shading  by  the  barley  crop  and  the  evapo- 
ration of  the  moisture  through  its  roots  and  leaves  had  prevented  the 
salts  from  reaching  the  surface  in  such  amounts  as  to  injure  the  crop, 
although  the  tendency  to  rise  was  clearly  shown. 


12 


UNIVERSITY   OP    CALIFORNIA— EXPERIMENT   STATION. 


Ten  feet  from  this  spot  was  bare  alkali  ground  on  which  barley  had 
refused  to  grow.  Its  examination  proved  it  to  contain  a  somewhat 
larger  proportion  (one-fifth  more)  of  alkali  salts,  and  in  these  a  larger 
relative  proportion  of  carbonate  of  soda  (salsoda).  Thus  the  seed  was 
mostly  destroyed  before  germination,  and  of  the  few  seedlings  none 
lived  beyond  the  fourth  leaf.  On  the  ground  represented  by  Fig.  1, 
previous  treatment  with  gypsum  had  so  far  diminished  the  salsoda 
that  the  grain  germinated  freely,  and  a  very  good  crop  of  barley  was 

Percentage  Composition. 


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FIG.  3.     Distribution  of  alkali  salts  in  sandy  land. 

harvested  there  without  irrigation.    The  same  season,  grain  crops  were 
almost  a  failure  on  alkali-free  land  in  the  same  region. 

In  connection  with  this  result  it  should  be  noted  as  a  general  fact 
that  alkali  lands  always  retain  a  certain  amount  of  moisture  perceptible 
to  the  hand  during  the  dry  season,  and  that  this  moisture  can  be  utilized 
by  crops;  so  that  at  times  when  crops  fail  on  nonalkaline  land,  good 
ones  are  obtained  where  a  slight  taint  of  alkali  exists  in  the  soil.  Strik- 
ing examples  of  this  fact  occur  in  the  Spokane  country  within  the  great 
bend  of  the  Columbia  River,  in  the  State  of  Washington;  and  the 
same  is  illustrated  by  the  luxuriant  growth  of  weeds  on  the  margin  of 


DISTRIBUTION  OF  ALKALI   SALTS. 


13 


alkali  spots,  just  beyond  the  limit  of  corrosive  injury.  Actual  deter- 
mination showed  that  while  a  sample  of  alkali  soil  containing  .54  per 
cent  of  salts  absorbed  12.3  per  cent  of  moisture  from  moist  air,  the 
same  soil  when  leached  absorbed  only  2.5  per  cent— a  figure  corre- 
sponding to  that  of  sandy  upland  loams.  Investigation  at  the  Tulare 
substation  during  the  dry  season  of  1898  also  showed  the  presence  of 
15  and  16  per  cent  of  water,  respectively,  in  strong  "white"  and 
"black"  alkali  soils,  while  in  adjoining  light  alkali  soils  there  was  but 
30  per  cent. 

In  very  sandy  lands,  and  particularly  when  the  alkali  is  "white" 
only,  the  tendency  to  accumulation  near  the  surface  is  much  less,  even 


Amounts  of  Alkali  Salts  i> 

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FIG.  4.    Distribution  of  alkali  salts  in  close-textured  soil  of  the  10-acre  tract,  near  Chino,  Cal. 

under  irrigation.  In  the  natural  condition  the  salts  are  in  such  cases 
often  found  quite  evenly  distributed  through  soil  columns  of  four  feet, 
and  even  more.  This  is  an  additional  cause  of  the  lesser  injuriousness 
of  "white"  alkali. 

Fig.  3  shows  the  distribution  of  the  salts  as  found  in  a  very  sandy 
area  on  the  Tulare  substation  grounds.  It  should  be  noted  that  here, 
while  the  general  figure  representing  the  distribution  is  very  similar  to 
that  showing  the  same  in  a  close  soil  (see  Fig.  4)  the  salts  reach  down 
to  over  six  feet,  and  are  at  their  maximum  eighteen  inches  from,  instead 
of  at  the  surface. 

The  mode  of  distribution  of  alkali  salts  in  the  heavier,  close-grained 
soil  of  the  Chino  tract  is  illustrated  in  Fig.  4.  As  has  been  mentioned, 
this  land  is  permanently  moist,  from  a  water-table  ranging  from  five  to 


14  UNIVERSITY    OF    CALIFORNIA— EXPERIMENT   STATION. 

seven  feet  below  the  surface  in  ordinary  years.  There  is  therefore  no 
opportunity  for  the  formation  of  "alkali  hardpan"  as  in  the  case  of 
the  Tulare  soil ;  the  salts  always  remain  rather  near  the  surface,  viz, 
within  twelve  to  eighteen  inches.  But  being  in  much  smaller  average 
amounts  than  at  Tulare  (an  average  of  about  5,300  pounds  per  acre), 
quite  a  copious  natural  vegetation  of  grasses,  sunflowers,  and  "verba 
mansa"  originally  covered  the  whole  surface,  save  in  a  few  low  spots. 

A  similar  mode  of  distribution  of  the  salts  is  found  in  the  more  clayey 
"black  adobe"  lands  of  the  Great  Valley  of  California.  The  scanty 
rains  can  not  penetrate  these  soils  to  any  great  depth,  so  that  evapora- 
tion will  soon  bring  the  salts  carried  by  them  back  to  within  a  short 
distance  of  the  surface.  Their  accumulation  there  is  frequently  indi- 
cated by  the  entire  absence  of  any  but  the  most  resistant  alkali  weeds, 
even  though  the  total  of  salts  in  the  land  may  not  be. very  great.* 

While  the  phenomena  of  alkali  lands  as  outlined  above  undoubtedly 
represent  the  vastly  predominant  conditions  on  extensive  level  lands, 
yet  there  are  exceptions  due  to  surface  conformation,  and  to  the  local 
existence  of  sources  of  alkali  salts  outside  of  the  soil  itself.  Such  is  the 
case  where  salts  ooze  out  of  strata  cropping  out  on  hillsides,  as  is 
the  case  at  some  points  in  the  San  Joaquin  Aralley  in  California,  and  in 
parts  of  Colorado,  Wyoming,  and  Montana.  In  such  cases  the  alkali 
salts  may  be  most  apparent  near  the  foot  of  the  hills,  and  in  light, 
well-drained  valley  lands  may  disappear  altogether  before  reaching  the 
valley-trough. 

On  the  other  hand,  it  not  infrequently  happens  that  in  sloping  val- 
leys or  basins,  where  the  central-  (lowest)  portion  receives  the  salts 
leached  out  of  the  adjacent  hills  and  valley  slopes  in  consequence  of 
slow  subdrainage,  we  find  belts  of  greater  or  less  width  in  which  the 
alkali  impregnation  may  reach  to  the  depth  of  ten  or  twelve  feet,  usually 
within  more  or  less  definite  layers  of  calcareous  hardpan,  likewise  the 
outcome  of  the  leaching  of  the  valley  slopes.  Such  areas,  however,  are 
usually  quite  limited,  and  are,  of  course,  scarcely  reclaimable  without 
excessive  expenditure,  the  more  as  they  are  often  underlaid  by  saline 
bottom  water.  In  these  cases  the  predominant  saline  ingredient  is 
usually  common  salt,  as  might  be  expected,  and  as  is  exemplified  on  a 
large  scale  in  the  Great  Salt  Lake  of  Utah,  and  in  the  ocean  itself. 

In  many  cases,  in  California  and  elsewhere,  the  over-irrigation  of 
bench  or  slope  lands  has  caused,  first  the  lower  slopes,  and  then  the 
bottom  lands  of  streams  and  rivers,  to  be  overrun  with  alkali  salts, 
although  before  irrigation  was  practiced  these  lands  were  exempt  from 
them.  In  some  portions  of  the  San  Joaquin  Valley  this  trouble  has 
become  most  serious,  fertile  lands  long  under  successful  cultivation 
being   rendered   useless   by   thousands   of   acres,    unless   an   expensive 


COMPOSITION   OF  ALKALI   SALTS.  15 

system  of  underdrainage  were  resorted  to.  Even  this  remedy  is  largely 
inapplicable  in  the  absence  of  legislation  providing  for  right-of-way 
for  drainage  as  well  as  for  irrigation;  bnt  any  such  legislation  should, 
at  the  same  time,  provide  a  remedy  for  the  leakage  of  ditch-water,  which 
is  the  original  cause  of  the  injury. 

COMPOSITION  OF  ALKALI  SALTS. 

Broadly  speaking,  it  may  be  said  that,  the  world  over,  alkali  salts 
consist  of  three  chief  ingredients,  namely,  common  salt,  glauber  salt 
(sulfate  of  soda),  and  salsoda  or  carbonate  of  soda.  The  latter 
causes  what  is  popularly  known  as  "black  alkali,"  from  the  black 
spots  or  puddles  seen  on  the  surface  of  lands  tainted  with  it,  owing  to 
the  dissolution  of  the  soil  humus;  while  the  other  salts,  often  together 
with  epsom  salt,  constitute  "white  alkali,"  which  is  known  to  be  very 
much  milder  in  its  effect  on  plants  than  the  black.  In  most  cases  all 
three  are  present,  and  all  may  be  considered  as  practically  valueless  or 
noxious  to  plant  growth.  Sulfate  of  magnesia  (epsom  salt)  and  the 
chlorids  of  magnesium  and  calcium  are  also  not  uncommon,  especially 
in  the  interior  region— Montana,  Wyoming,  Colorado,  Utah,  and  New 
Mexico,  where  the  first-named  sometimes  forms  the  predominant  ingre- 
dient.    They  also  are  found  in  California. 

With  these  noxious  salts,  however,  there  are  almost  always  associated, 
in  varying  amounts,  sulfate  of  potash,  phosphate  of  soda,  and  nitrate 
of  soda,  representing  the  three  elements— potassium,  phosphorus,  and 
nitrogen — upon  the  presence  of  which  in  the  soil,  in  available  form, 
the  welfare  of  our  crops  so  essentially  depends,  and  which  we  aim 
to  supply  in  fertilizers.  The  potash  salt  is  usually  present  to  the 
extent  of  from  5  to  20  per  cent  of  the  total  salts;  phosphate,  from  a 
fraction  to  as  much  as  4  per  cent;  the  nitrate,  from  a  fraction  to  as 
much  as  20  per  cent.  In  black  alkali  the  nitrate  is  usually  low,  the 
phosphate  high;  in  the  white,  the  reverse  is  true. 

It  is  thus  clear  that  if  we  were  to  make  a  rule  of  reclaiming  alkali 
lands  by  leaching  out  the  salts  with  an  abundance  of  irrigation  water,  we 
would  get  rid  not  only  of  the  noxious  salts,  but  also  of  those  ingredients 
upon  which  productiveness  primarily  depends,  and  for  which  we  pay 
heavily  in  fertilizers.     This  is  evidently  to  be  avoided,  if  possible. 

Summing  up  the  conclusions  from  the  foregoing  observations  and 
considerations  we  find  that— 

(1)  The  amount  of  soluble  salts  in  alkali  soils  is  usually  limited; 
they  are  not  ordinarily  supplied  in  indefinite  quantities  from  the 
bottom  water  below.  These  salts  have  mostly  been  formed  by  weather- 
ing, in  the  soil  layer  itself. 


16  UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 

(2)  The  salts  ordinarily  move  up  and  down  within  the  upper  four 
or  five  feet  of  the  soil  and  subsoil,  following  the  movement  of  the  mois- 
ture ;  descending  in  the  rainy  season  to  the  limit  of  the  annual  moisten- 
ing as  a  maximum,  and  then  reascending  or  not  according  as  surface 
evaporation  may  demand.  At  the  end  of  the  dry  season,  in  untilled 
irrigated  land,  practically  the  entire  mass  of  salts  may  be  within  six  or 
eight  inches  of  the  surface. 

(3)  The  injury  to  vegetation  is  caused  mainly,  sometimes  wholly, 
within  a  few  inches  of  the  surface,  by  the  corrosion  of  the  bark,  usually 
near  the  root  crown.  This  corrosion  is  strongest  when  carbonate  of  soda 
(salsoda)  forms  a  large  proportion  of  the  salts;  the  soda  then  also  dis- 
solves the  vegetable  mold  and  causes  blackish  spots  in  the  soil,  popu- 
larly known  as  black  alkali. 

(4)  The  injury  caused  by  carbonate  of  soda  is  aggravated  by  its 
action  in  puddling  the  soil  so  as  to  cause  it  to  lose  its  flaky  condition, 
rendering  it  almost  or  quite  untillable.  It  also  tends  to  form  in  the 
depths  of  the  soil  layer  a  tough  hardpan,  impervious  to  water,  which 
yields  to  neither  plow,  pick,  nor  crowbar,  and  renders  drainage  and 
leaching  impossible.  Its  presence  is  easily  ascertained  by  means  of  a 
pointed  steel  sounding  rod. 

(5)  While  alkali  lands  share  with  other  soils  of  the  arid  region  the 
advantage  of  unusually  high  percentages  of  plant-food  in  the  insoluble 
form,*  they  also  contain,  alongside  of  the  noxious  salts,  considerable 
amounts  of  water-soluble  plant-food.  When,  therefore,  the  action  of  the 
noxious  salts  is  done  away  with,  they  should  be  profusely  and  lastingly 
productive;  particularly  as  they  are  always  naturally  somewhat  moist 
in  consequence  of  the  attraction  of  moisture  by  the  salts,  and  are  there- 
fore less  liable  to  injury  from  drought  than  the  same  soils  when  free 
from  alkali. 

UTILIZATION  AND  RECLAMATION  OF  ALKALI  LANDS. 

The  most  obvious  mode  of  utilizing  alkali  lands  is  to  occupy  them 
with  useful  plants  that  are  not  affected  by  the  noxious  salts.  Unfortu- 
nately, as  has  already  been  stated,  but  few  such  crops  of  general  utility, 
especially  for  the  commercial  and  labor  conditions  of  this  country,  have 
as  yet  been  found.  Practically  the  most  important  problem  is  to  render 
these  lands  available  for  our  ordinary  cultures,  by  methods  financially 
possible. 

Counteracting  Evaporation.— Since  evaporation  of  the  soil  moisture 
at  the  surface  is  what  brings  the  alkali  salts  to  the  level  where  the 
main  injury  to  plants  occurs,  it  is  obvious  that  evaporation  should  be 

*See  Bulletin  No.  3  of  the  U.  S.  Weather  Bureau,  1892;  Report  California  Station, 
1894-5. 


RECLAMATION   OF   ALKALI   LANDS.  17 

prevented  as  much  as  possible.  This  is  the  more  important,  as  the 
saving  of  soil  moisture,  and  therefore  of  irrigation  water,  is  attainable 
by  the  same  means. 

Three  methods  for  this  purpose  are  usually  practiced  by  farmers  and 
gardeners,  viz,  shading,  mulching,  and  the  maintenance  of  loose  tilth 
in  the  surface  soil  to  such  depth  as  may  be  required  by  the  climatic 
conditions. 

Mulching  is  already  well  recognized  in  the  alkali  regions  of  California 
as  an  effective  remedy  in  light  cases.  Fruit  trees  are  frequently  thus 
protected,  particularly  while  young,  after  which  their  shade  alone  may 
(as  in  the  case  of  low-trained  orange  trees)  suffice  to  prevent  injury. 
The  same  often  happens  in  the  case  of  low-trained  vines,  small  fruits, 
and  vegetables.  Sanding  of  the  surface  to  the  depth  of  several  inches 
was  among  the  first  attempts  in  this  direction;  but  the  necessity  of 
cultivation,  involving  the  renewal  of  the  sand  each  season,  renders 
this  a  costly  method.  Straw,  leaves,  and  manure  have  been  more 
successfully  used;  but  even  these,  unless  employed  for  the  purpose  of 
fertilization,  involve  more  expense  and  trouble  than  the  simple  mainte- 
nance of  very  loose  tilth  of  the  surface  soil  throughout  the  dry  season; 
a  remedy  which,  of  course,  is  equally  applicable  to  hoed  field  crops, 
and  in  the  case  of  some  of  these— e.  g.,  cotton— is  a  necessary  condition 
of  cultural  success  everywhere.  The  wide  prevalence  of  " light"  and 
deep  soils  in  the  arid  regions,  from  causes  inherent  in  the  climate 
itself,*  renders  this  condition  of  relatively  easy  fulfillment. 

Diluting  the  Alkali  Salts.— Aside,  however,  from  the  mere  preven- 
tion of  surface  evaporation,  another  favorable  condition  is  realized  by 
this  procedure,  namely,  the  commingling  of  the  heavily  salt-charged 
surface  layers  with  the  relatively  nonalkaline  subsoil.  Since  in  the  arid 
regions  the  roots  of  all  plants  retire  farther  from  the  surface  because  of 
the  deadly  drought  and  heat  of  summer,  it  is  possible  to  cultivate 
deeper  than  could  safely  be  done  with  growing  crops  in  humid  climates. 
Yet  even  here,  the  maxim  of  "deep  preparation  and  shallow  culti- 
vation ' '  is  put  into  practice  with  advantage,  only  changing  the  measure- 
ments of  depth  to  correspond  with  the  altered  climatic  conditions. 
Thus,  while  in  the  eastern  United  States  four  inches  is  the  accepted 
standard  of  depth  for  summer  cultivation  to  preserve  moisture  without 
injury  to  the  roots,  that  depth  must  in  the  arid  region  frequently  be 
doubled  in  order  to  be  effective,  and  will  even  then  scarcely  touch  a 
living  root  in  orchards  and  vineyards  in  unirrigated  land. 

A  glance  at  Fig.  1  (p.  9)  will  show  the  great  advantage  of  extra 
deep  preparation  in  commingling  the  alkali  salts  accumulated  near 
the  surface  with  the  lower  soil  layers,  diffusing  the  salts  through  twelve 

*See  reference  on  preceding  page. 

2— bul.  128-133 


18  UNIVERSITY    OF    CALIFORNIA— EXPERIMENT    STATION. 

instead  of  six  inches  of  soil  mass.  This  will  in  very  many  cases  suffice 
to  render  the  growth  of  ordinary  crops  possible  if,  by  subsequent  fre- 
quent and  thorough  cultivation,  surface  evaporation,  and  with  it  the 
reascent  of  the  salts  to  the  surface,  is  prevented.  A  striking  example 
of  the  efficiency  of  this  mode  of  procedure  was  given  at  the  Tulare 
substation,  where  a  portion  of  a  very  bad  alkali  spot  was  trenched  to 
the  depth  of  two  feet,  throwing  the  surface  soil  to  the  bottom.  The  spot 
thus  treated  produced  excellent  wheat  crops  for  a  few  years— the  time 
it  took  the  alkali  salts  to  reascend  to  the  surface. 

It  should  therefore  be  kept  in  mind  that  whatever  else  is  done  toward 
reclamation,  deep  preparation  and  thorough  surface  cultivation  must 
be  regarded  as  prime  factors  for  the  maintenance  of  production  on  all 
alkali  lands. 

The  efficacy  of  shading,  already  referred  to,  is  strikingly  illustrated 
in  the  case  of  some  field  crops  which,  when  once  established,  will 
thrive  on  fairly  strong  alkali  soil,  provided  that  a  good  thick  "stand" 
has  once  been  obtained.  This  is  notably  true  of  the  great  forage  crop 
of  the  arid  region,  alfalfa,  or  lucern.  Its  seed  is  extremely  sensitive  to 
black  alkali,  and  will  decay  in  the  ground  unless  protected  against  it. 
But  when  once  a  full  stand  has  been  obtained,  the  field  may  endure  for 
many  years  without  a  sign  of  injury.  Here  two  effects  combine,  viz, 
the  shading,  and  the  evaporation  through  the  deep  roots  and  abundant 
foliage,  which  alone  prevents,  in  a  large  measure,  the  ascent  of  the 
moisture  to  the  surface.  The  case  is  then  precisely  parallel  to  that  of 
the  natural  soil  (see  Fig.  2),  except  that,  as  irrigation  is  practiced  in 
order  to  stimulate  production,  the  sheet  of  alkali  hardpan  will  be  dis- 
solved and  its  salts  spread  through  the  soil  more  evenly.  The  result  is 
that  oftentimes,  so  soon  as  the  alfalfa  is  taken  off  the  ground  and  the 
cultivation  of  other  crops  is  attempted,  an  altogether  unexpectedly  large 
amount  of  alkali  comes  to  the  surface  and  greatly  impedes,  if  it  does 
not  altogether  prevent,  the  immediate  planting  of  other  crops.  Shallow- 
rooted  annual  crops  that  give  but  little  shade,  like  the  cereals,  while 
measurably  impeding  the  rise  of  the  salts  during  their  growth,  fre- 
quently allow  of  enough  rise  after  harvest  to  prevent  reseeding  the 
following  season. 

Chemical  Remedies.  — Of  the  three  sodium  salts  that  usually  consti- 
tute the  bulk  of  "alkali,"  only  the  carbonate  of  soda  is  susceptible  of 
being  materially  changed  by  any  agent  that  can  practically  be  applied 
to  land.  So  far  as  we  know,  the  salt  of  sodium  least  injurious  to 
ordinary  vegetation  is  the  sulfate,  commonly  called  glauber  salt,  which 
ordinarily  forms  the  chief  ingredient  of  white  alkali.  Thus  barley  is 
capable  of  resisting  about  five  times  more  of  the  sulfate  than  of  the 
carbonate,  and  quite  twice  as  much  as  of  common  salt.     Since  the 


RECLAMATION   OF   ALKALI   LANDS. 


19 


maximum  percentage  that  can  be  resisted  by  plants  varies  materially 
with  the  kind  of  soil,  it  is  difficult  to  give  exact  figures  save  with  respect 
to  particular  cases.  For  the  sandy  loam  of  the  Tulare  substation  the 
maximum  for  cereals  may  be  approximately  stated  to  be  one  tenth  of 
one  per  cent  (0.1)  for  salsoda,  a  fourth  of  one  per  cent  (0.25)  for 
common  salt,  and  from  forty-five  to  fifty  one  hundredths  of  one  per 
cent  (0.45-.50)  for  glauber  salt,  within  the  first  foot  from  the  surface. 
For  clay  soils  the  tolerance  is  markedly  less,  especially  as  regards  the 
salsoda,  since  in  their  case  the  injurious  effect  on  the  tilling  qualities 
cf  the  soil,  already  referred  to,  is  superadded  to  the  corrosive  action  of 


F[G.  5.    Wheat  growing  3  feet  high  in  soil  crusted  with  white  alkali,  originally  a  barren 
black-alkali  spot  but  reclaimed  with  gypsum.    Tulare  Experiment  Substation. 

that  salt;  and  in  them,  moreover,  accumulation  at  the  surface  is  more 
pronounced. 

Since,  then,  so  little  carbonate  of  soda  suffices  to  render  soils  un- 
cultivable,  it  frequently  happens  that  its  mere  transformation  into 
the  sulfate  is  sufficient  to  remove  all  stress  from  alkali.  Gypsum 
(land-plaster)  is  the  cheapest  and  most  effective  agent  to  bring  about 
this  transformation,  provided  ivater  be  also  present.  The  amount 
required  per  acre  will,  of  course,  vary  with  the  amount  of  carbonate 
of  soda  in  the  soil,  all  the  way  from  a  few  hundred  pounds  to  several 
tons  in  the  case  of  strong  alkali  spots.  But  it  is  not  usually  necessary 
to  add  the  entire  quantity  at  once,  provided  that  sufficient  be  used  to 
neutralize  the  alkali  near  the  surface,  and  enough  time  be  allowed  for 
the  action  to  take  place.  In  very  wet  soils  this  may  occur  within  a  few 
days;  in  merely  damp  soils,  in  the  course  of  months;  but  usually  the 


20  UNIVERSITY   OF    CALIFORNIA— EXPERIMENT   STATION. 

effect  increases  for  years,  as  the  salts  rise  from  below.  For  the  com- 
plete neutralization  of  each  1,000  pounds  of  carbonate  of  soda  in  the 
land,  1,630  pounds  of  pure  gypsum  is  required.  But  of  the  impure, 
80-85  per  cent  article  as  now  on  the  market  in  California,  an  even  double 
quantity,  or  2,000  pounds,  would  be  the  proper  dose. 

The  effect  of  gypsum  on  the  black-alkali  soil  of  Tulare  substation 
was  to  change  a  barren  spot  into  a  tract  which  produced  a  fine  crop  of 
wheat,  although  the  surface  of  the  soil  was  covered  with  a  crust  of  the 
white  alkali  (sulfate  of  soda).  This  is  shown  in  the  photograph 
(Fig.  5)  on  preceding  page. 

The  effect  of  gypsum  on  black  alkali  land  is  often  very  striking, 
even  to  the  eye.  The  blackish  puddles  and  spots  disappear,  because 
the  gypsum  renders  the  dissolved  humus  insoluble  and  thus  restores  it 
to  the  soil.  The  latter  soon  loses  its  hard,  puddled  condition  and 
crumbles  and  bulges  into  a  loose  mass,  into  which  water  now  soaks 
freely,  bringing  up  the  previously  depressed  spots  to  the  general  level 
of  the  land,  and  permitting  free  subdrainage.  On  the  surface  thus 
changed  seeds  now  germinate  and  grow  without  hindrance;  and  as  the 
injury  from  alkali  occurs  at  or  near  the  surface,  it  is  usually  best  to 
simply  harrow-in  the  plaster,  leaving  the  water  to  carry  it  down  in 
solution.  Soluble  phosphates  present  are  decomposed,  so  as  to  retain 
finely  divided  but  less  soluble  phosphates  in  the  soil. 

Trees  and  vines  already  planted  may  be  temporarily  protected  from 
the  worst  effects  of  the  black  alkali  by  surrounding  the  trunks  with 
gypsum  or  with  earth  abundantly  mixed  with  it.  Seeds  may  be  simi- 
larly protected  in  sowing,  and  plants  in  planting. 

It  must  not  be  forgotten  that  this  beneficial  change  effected  by  the 
gypsum  may  go  backward  if  the  land  thus  treated  is  permitted  to  be 
swamped  by  excess  of  irrigation  water  or  otherwise.  Under  the  same 
conditions  alkali  naturally  white  may  turn  to  black;  and  no  amount 
of  gypsum  used  can  prevent  or  undo  this  until  the  excess  of  water  is 
drained  off  and  the  soil  allowed  time  for  aeration.  Thus  while  exces- 
sive irrigation  is  injurious  at  all  times  in  diminishing  the  death  of  root- 
growth  and  the  feeding  area  of  the  plant,  it  is  especially  injurious 
when  alkali  is  present. 

Of  course  gypsum  is  of  no  benefit  whatever  on  soils  containing  no 
salsoda,  but  only  glauber  and  common  salt.  f 

Stable  Manure  and  Other  Fertilizers.— Under  the  impression  that 
alkali  land  is  poor  in  plant-food,  farmers  frequently  try  applications 
of  stable  manure  and  other  fertilizers.  As  a  rule  these  applications  are 
not  only  useless,  but  even  harmful.  From  their  very  mode  of  forma- 
tion, alkali  lands  are  exceptionally  rich  in  plant-food,  so  that  the 
addition  of  more  can  do  no  good.    In  the  case  of  stable  manure  being 


REMOVING  ALKALI  SALTS  FROM  THE  SOIL.  21 

used  on  black  alkali  ground,  a  pungent  odor  of  ammonia  is  given  off 
whenever  the  sun  shines,  and  plants  otherwise  doing  well  are  thus 
injured  or  killed.  When  well  plowed-in,  stable  manure  will  sometimes 
jprevent  to  some  extent  the  rise  of  the  alkali  by  diminishing  evaporation ; 
but  its  usefulness  in  that  respect  is  readily  replaced  by  good  tillage. 
The  main  benefit  obtained  is  the  addition  of  humus  to  soils  that  have 
been  whitened  by  alkali  action. 

Potash  salts,  especially  kainit,  are  wholly  useless  and  add  to  the 
alkali  trouble ;  potash  is  always  abundantly  present  in  alkali  lands, 
even  in  the  water-soluble  condition.  Nitrates,  also,  are  always  present 
in  alkali  soils  in  sufficient  amounts  for  plant  growth,  sometimes  to 
excess.  Phosphates  may  sometimes  be  useful,  but  will  rarely  be  needed 
for  some  years.  Greenmanuring,  on  the  other  hand,  is  a  very  desirable 
improvement  on  all  alkali  lands. 

REMOVING  THE  SALTS  PROM  THE  SOIL. 

In  case  the  amount  of  salts  in  the  soil  should  be  so  great  that  even 
the  change  worked  by  gypsum  is  insufficient  to  render  it  available  for 
useful  crops,  the  only  remedy  left  is  to  remove  the  salts  partially  or 
wholly  from  the  land. 

Two  chief  methods  are  available  for  this  purpose.  One  is  to  remove 
the  salts,  with  more  or  less  earth,  from  the  surface  at  the  end  of  the 
dry  season,  either  by  sweeping,  or  by  means  of  a  horse  scraper  set  so  as 
to  carry  off  a  certain  depth  of  soil.  Thus  sometimes  in  a  single  season 
one  third  or  one  half  of  the  total  salts  may  be  got  rid  of,  the  loss  of  a 
few  inches  of  surface  soil  being  of  little  moment  in  the  deep  soils  of  the 
arid  region.  On  small  tracts,  as  in  gardens,  this  can  be  very  effectively 
done. 

The  other  method  is  to  leach  down  the  salts  by  flooding;  either  into 
the  country  drainage,  which  will  afford  definitive  relief,  supplementing 
by  irrigation  water  what  is  left  undone  by  the  deficient  rainfall;  or 
else  to  a  depth  sufficient  to  allow  seeds  to  sprout  so  as  to  produce  a  good 
stand  without  injury  from  alkali,  and  then  to  keep  the  latter  down  by 
means  of  irrigation  in  deep  furrows— the  use  of  shallow  furrows  as 
usually  made  will  rapidly  bring  the  salts  to  the  surface  again  by 
evaporation— or  in  the  case  of  broadcast  cultures,  by  repeated  flooding. 
When  the  salts  have  once  been  washed  down  to  the  depth  of  several 
feet  by  flooding,  the  conscientious  practice  of  deep-furrow  irrigation 
can  be  made  to  keep  them  out  of  reach  indefinitely,  or  until  underdrains 
can  be  afforded. 

It  is  not  practicable,  as  many  suppose,  to  wash  the  salts  off  the  sur- 
face by  a  rush  of  water,  as  they  instantly  soak  into  the  ground  at  the 
first  touch.    Nor  is  there  any  sensible  relief  from  allowing  the  water  to 


22  UNIVERSITY   OF    CALIFORNIA— EXPERIMENT   STATION. 

stand  on  the  land  and  then  drawing  it  off;  in  this  case  also  the  salts 
soak  down  ahead  of  the  water,  and  the  water  standing  on  the  surface 
remains  almost  unchanged.  In  very  pervious  soils,  and  in  the  ease  of 
white  alkali,  the  washing-out  can  often  be  accomplished  without  special 
provision  for  underdrainage,  by  leaving  the  water  on  the  land  suffi- 
ciently long.  But  the  laying  of  regular  underdrains  greatly  accelerates 
the  work,  and  renders  success  certain.  In  the  case  of  black  alkali, 
however,  either  the  impervious  hardpan  or  (in  the  case  of  actual  alkali 
spots)  the  impenetrability  of  the  surface  soil  itself  will  render  even 
underdrains  ineffective  unless  the  salsoda  and  its  effects  on  the  soil 
are  first  destroyed  by  the  use  of  gypsum,  as  above  detailed.  This  is 
not  only  necessary  in  order  to  render  drainage  and  leaching  possible, 
but  is  also  advisable  in  order  to  prevent  the  leaching-ont  of  the  valuable 
humus  and  soluble  phosphates,  which  are  rendered  insoluble  (but  not 
unavailable  to  plants)  by  the  action  of  the  gypsum.  Wherever  black 
alkali  is  found,  in  considerable  proportion,  the  application  of  gypsum 
should  precede  any  and  all  other  efforts  toward  reclamation. 

Another  method  for  diminishing  the  amount  of  alkali  in  the  soil  is 
the  cropping  with  plants  that  take  up  considerable  amounts  of  salts. 
In  taking  them  into  cultivation,  it  is  advisable  to  remove  entirely  from 
the  land  the  salt  growth  that  may  naturally  cover  it,  notably  the 
bushy  samphire  and  greasewood  (Allenrolfea,  Sarcdbatus) ,  with  their 
heavy  percentages  of  alkaline  ash.  Crop  plants  adapted  to  the  same 
object  are  mentioned  farther  on. 

The  effect  of  removing  the  alkali  salts  from  the  surface  soil  to  a  depth 
beyond  the  tree  roots  by  the  liberal  use  of  irrigation  water  was  well 
shown  in  a  lemon  orchard  near  La  Mirada,  Los  Angeles  County,  where 
some  of  the  trees  were  badly  stunted  by  the  presence  of  about  3,800 
pounds  of  carbonate  of  soda  and  common  salt.  The  manager,  by  an 
excessive  use  of  water,  dissolved  the  salts  and  caused  them  to  be  carried 
down  deeply  beyond  the  roots,  and  the  result  shortly  was  apparent 
in  the  improved  growth  and  condition  of  the  trees.  The  accompanying 
photographs  were  taken  before  and  after  the  treatment,  and  the  change 
from  poor  to  good  condition  is  well  shown. 

WILL   IT   PAY   TO   RECLAIM   ALKALI   LANDS  ? 

This  is  a  question  naturally  asked  when  considering  the  nature  and 
expense  of  the  operation  involved,  especially  when  the  last  resort— 
underdraining  and  leaching— has  to  be  adopted. 

Those  familiar  with  the  alkali  regions  are  aware  how  often  the 
occurrence  of  alkali  spots  interrupts  the  continuity  of  fields  and 
orchards,  of  which  they  form  only  a  small  part,  but  enough  to  mar  their 
aspect  and  cultivation.     Their  increase  and  expansion  under  irrigation 


FIG  6.    Lemon  orchard  affected  by  alkali  before  deep  irrigation. 


FIG.  7.    The  above  orchard  after  alkali  was  driven  down  by  deep  irrigation,  followed  by 

cultivation. 


24  UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 

frequently  render  their  reclamation  the  only  alternative  of  absolute 
abandonment  of  the  investments  and  improvements  made,  and  from 
that  point  of  view  alone  it  is  of  no  slight  practical  importance.  More- 
over, the  occurrence  of  vast  continuous  stretches  of  alkali  lands  within 
the  otherwise  most  eligibly  situated  portions  of  the  irrigation  region 
forms  a  strong  incentive  toward  their  utilization. 

There  is,  however,  a  strong  intrinsic  reason  pointing  in  the  same 
direction,  namely,  the  almost  invariably  high  and  lasting  productive- 
ness of  these  lands  when  once  rendered  available  to  agriculture.  This 
is  foreshadowed  by  the  usually  very  heavy  and  luxuriant  growth  of 
native  plants  around  the  margins  of  and  between  alkali  spots  (see 
Fig.  8)  ;  that  is,  wherever  the  amount  of  injurious  salts  present  is  so 
small  as  not  to  interfere  with  the  utilization  of  the  abundant  store  of 
plant-food  which,  under  the  peculiar  conditions  of  soil  formation  in 
arid  climates,  remains  in  the  land  instead  of  being  washed  into  the 
ocean.  Extended  comparative  investigations  of  soil  composition,  as 
well  as  the  experience  of  thousands  of  years  in  the  oldest  settled 
countries  of  the  world,  demonstrate  this  fact  and  show  that,  so  far  from 
being  in  need  of  fertilization,  alkali  lands  possess  extraordinary  pro- 
ductive capacity  whenever  freed  from  the  injurious  influence  of  the 
excess  of  useless  salts  left  in  the  soil  in  consequence  of  deficient  rainfall. 
Alkali  salts  are  actually  scraped  up  and  carried  to  the  cultivated  fields 
in  sacks  in  parts  of  Turkestan,  the  peasants  considering  that  "the 
salt  is  the  life  of  the  land."     (Middendorf.) 

It  does  not,  of  course,  follow  that  alkali  lands  are  good  lands  for 
farmers  of  limited  means  to  settle  upon.  On  the  contrary,  like  most 
other  business  enterprises,  they  require  a  certain  amount  of  capital 
and  lapse  of  time  to  render  them  productive.  They  are  not,  therefore,  a 
proper  investment  for  farmers  or  settlers  of  small  means,  dependent  on 
annual  crops  for  their  livelihood  and  unable  to  bring  to  bear  upon  these 
soils  the  proper  means  for  their  reclamation ;  unless,  indeed,  local  con- 
ditions should  enable  them  to  use  successfully  some  of  the  crops  specially 
adapted  to  alkali  lands. 

CROPS   SUITABLE   FOR   ALKALI   LANDS. 

As  has  already  been  stated,  the  search  for  generally  available  crops 
that  will  thrive  in  strong,  unreclaimed  alkali  land  has  not  thus  far 
been  very  successful.  It  is  true  that  cattle  will  nibble  alkali  grass 
(Distichlis  spicata) ,  but  will  soon  leave  it  for  any  dry  food  that  may  be 
within  reach.  The  same  is  true  of  all  the  fleshy  plants  that  grow  on 
the  stronger  alkali  lands,  and  are  known  under  the  general  designation 
of  alkali  weeds.  When  stock  unaccustomed  to  it  are  forced  by  hunger 
to   feed   on   such   vegetation   to   any   considerable   extent,    disordered 


m 


26  UNIVERSITY    OF    CALIFORNIA  — EXPERIMENT    STATION. 

digestion  is  apt  to  result;  which,  in  such  ranges,  however,  is  often 
counteracted  by  feeding  on  aromatic  or  astringent  antidotes,  such  as 
the  gray  sagebrush  and  the  more  or  less  resinous  herbage  of  plants  of 
the  sunflower  family.  In  the  Great  Basin  region,  lying  between  the 
Sierra  Nevada  and  the  front  range  of  the  Rocky  Mountains,  there  are, 
aside  from  the  grasses,  numerous  herbaceous  and  shrubby  plants  that 
afford  valuable  pasturage  for  stock,*  and  some  of  these  grow  on  mod- 
erately strong  alkali  land;  the  same  is  true  in  California.  It  is  quite 
possible  that  some  of  these  will  be  found  to  lend  themselves  to  ready 
propagation  for  culture  purposes  as  well  as  they  do  for  restocking  the 
ranges.  But  thus  far  none  have  found  wider  acceptance,  probably 
because  their  stiff  branches  and  upright  habit  render  them  inconvenient 
to  handle.  It  will  require  more  extended  experience  and  experiment 
before  any  of  these  can  be  definitely  adopted  by  farmers. 

Experience  in  California  indicates  that  in  the  more  southerly  portion 
of  the  arid  region  the  unpalatable  native  plants  may  be  generally 
replaced,  even  on  the  ranges,  by  one  or  more  species  of  the  Australian 
saltbushes  (Atriplex  spp.),  long  ago  recommended  by  Baron  von  Mueller 
of  Melbourne;  of  which  one  (A.  semibaccata)  has  proved  eminently 
adapted  to  the  climate  and  soil  of  California  and  is  readily  eaten  by 
all  kinds  of  stock.  The  facility  with  which  it  is  propagated,  its  quick 
development,  the  large  amount  of  feed  yielded  on  a  given  area,  even 
in  the  strongest  alkali  land  ordinarily  found,  and  its  thin,  flexible  stems, 
permitting  it  to  be  handled  very  much  like  alfalfa,  seem  to  commend 
it  especially  to  the  farmer's  consideration  wherever  the  climate  will 
^permit  of  its  use.  Its  resistance  to  severe  cold  weather  has  not  yet 
been  adequately  tested.  It  is  probable  that  other  species,  now  also 
under  trial,  will  equally  justify  the  recommendation  given  them  by 
the  eminent  botanist  who  first  brought  them  into  public  notice  as 
promising  forage  plants.  Most  of  the  species  have  an  upright,  shrubby 
habit  which  adapts  them  rather  to  browsing  than  to  use  as  a  forage 
crop.  Among  the  best  next  to  the  semibaccata  are  the  species  leptocarpa 
and  halimoides,  the  former  somewhat  similar  in  habit  to  the  semibaccata 
but  not  so  rapid  a  grower.  The  A.  nummularia  (old-man  saltbush), 
highly  valued  and  recommended  in  Australia  and  Algeria,  is  not  liked 
by  California  stock;  but  the  species  cachiyouyo,  introduced  from 
Argentina,  seems  to  be  palatable  to  all  kinds  of  stock,  and  but  for  its 
tall,  upright  habit,  would  be  among  the  most  acceptable  of  the  salt- 
bushes,  being  very  productive. 

A  special  bulletin  on  the  saltbushes,  Australian  as  well  as  native,  has 
been  published  by  this  Station  and  will  be  sent  on  request. 

*See  Bulletin  No.  16  of  the  Wyoming  Experiment  Station;  also  Bulletins  Nos.  2 
and  12  of  the  Division  of  Agrostology,  and  Farmers'  Bulletin  No.  108,  U.  S.  Depart- 
ment of  Agriculture. 


28  UNIVERSITY   OF    CALIFORNIA— EXPERIMENT   STATION. 

It  is  to  be  noted  that  since  the  saltbushes  take  up  nearly  one  fifth  of 
their  dry  weight  of  ash  ingredients,*  largely  common  salt,  the  complete 
removal  from  the  land  of  a  five-ton  crop  of  saltbush  hay  will  take  away 
nearly  a  ton  of  the  alkali  salts  per  acre.  This  will  in  the  course  of 
some  years  be  quite  sufficient  to  reduce  materially  the  saline  contents 
of  the  land,  and  will  frequently  render  possible  the  culture  of  ordinary 
crops. 

Next  to  the  saltbushes  the  Chilean  plant  Modiola  decumbens  (now 
commonly  known  as  modiola  simply) ,  of  the  mallow  family,  deserves 
attention.  Accidentally  introduced  as  a  weed  with  other  seeds,  by  the 
Kern  County  Land  Company  at  Bakersfield,  it  attracted  attention  by 
its  persistence  on  alkali  lands,  and  by  the  observation  that  cattle  ate  it 
freely.  It  was  then  grown  on  a  larger  scale,  and  found  to  make  accep- 
table pasture  where  alfalfa  could  not  be  grown  on  account  of  alkali. 
It  is  a  trailing  plant,  with  medium-sized,  roundish  foliage,  and  roots 
freely  at  the  joints  where  they  touch  the  ground.  Unlike  the  saltbushes 
it  is  therefore  a  formidable  weed  where  it  is  not  wanted;  but  as, 
according  to  our  determinations,  it  resists  as  much  as  52,000  pounds  of 
salts  per  acre,  even  when  41,000  of  these  is  common  salt,  it  is  likely  to 
be  useful  in  many  cases,  particularly  as  an  admixture  to  a  saltbush  diet 
for  stock,  the  more  as  it  does  not  absorb  as  much  salt  as  the  latter. 
Owing  to  the  rooting  habit  of  the  stems,  it  is  not  as  convenient  to 
handle  as  the  semibaccata  saltbush,  nor,  probably,  will  it  yield  as  much 
fodder  in  a  season.    It  seems  best  adapted  to  pasturage. 

Another  forage  plant  which  it  may  hereafter  pay  to  propagate  arti- 
ficially on  strong  alkali  land,  is  the  tussock-grass  (Sporobolus  airoides) , 
of  which  a  figure  is  given  on  page  63.  Indicating  as  it  usually  does 
when  growing  naturally,  land  too  strongly  impregnated  to  be  reclaimable 
at  this  time,  but  being  freely  eaten  by  stock,  it  seems  worth  while  to 
count  it  among  the  possible  pasture  grasses  for  land  too  strongly 
alkaline  to  bear  ordinary  crops.  Its  seed  can  be  abundantly  gathered 
in  its  native  habitats,  indicated  below. 

TOLERANCE  OF  ALKALI  BY  VARIOUS  CULTURES. 

In  1898-1900  we  made  special  investigations  on  this  subject  and 
have  endeavored  to  ascertain,  as  far  is  possible,  the  highest  amount  of 
each  salt  occurring  in  four  feet  depth  in  which  the  different  cultures 
of  all  kinds— orchard,  as  well  as  others— will  grow  and  come  to  matur- 
ity; for  while  it  is  true  that  it  is  the  alkali  within  the  first  foot  or  two 
of  the  surface  that  is  liable  to  produce  the  chief  injury  upon  the  roots 

♦Analyses  made  at  the  California  station  show  19.37  per  cent  of  ash  in  the  air-dry 
matter  of  Australian  saltbush.  (See  California  Sta.  Bui.  105;  E.  S.  R.,  vol.  6, 
p.  718.)  Analyses  of  Russian  thistle  have  been  reported  showing  over  20  per  cent 
of  ash  in  dry  matter.  (See  Minnesota  Sta.  Bui.  34;  Iowa  Sta.  Bui.  26;  E.  S.  R., 
vol.  6,  pp.  552,  553.) 


TOI^ERANCE  of  alkali  by  various  cultures.  29 

of  the  plants,  it  is  certain  that  there  will  come  a  time  in  the  cultivation 
of  the  land  when  nearly  all  of  the  salts  that  lie  in  the  lower  depths 
of  the  soil  will  be  reached  and  dissolved  by  the  water  that  has  been 
given  to  the  soil  either  by  rainfall  or  by  irrigation  in  sufficient  amounts 
to  percolate  downward  to  it,  and  will  be  brought  up  and  concentrated 
at  or  near  the  surface.  This  has  occurred  in  the  substations  at  Tulare 
and  Chino. 

It  is  this  concentration  that  has  proved  so  destructive  to  many  cul- 
tures that  for  a  time  have  done  well ;  and  it  is  this  total  amount  within 
reach  of  water  that  must  be  considered  when  orchard  trees  or  perennial 
crops  are  planted,  if  the  farmer  wishes  to  avoid  the  agony  of  seeing  his 
work  and  hopes  of  years  swept  away  by  the  sudden  activity  of  an  enemy 
which  has  been  hidden  in  the  lower  depths  of  his  land. 

All  of  this  injury  to  cultures  was  at  first  naturally  attributed  either 
to  the  content  of  carbonate  of  soda  in  the  surface  foot,  where  its 
corrosive  action  on  the  tender  bark  of  the  root  crown  could  be  felt,  or 
to  the  very  large  amount  of  total  salts  which  might  produce  stagnation 
of  the  sap  or  other  injury  to  the  feeding  rootlets.  Some  analyses  and 
observations  were  made  at  that  time  both  on  the  amounts  of  alkali 
which  caused  suffering,  and  on  the  amounts  in  soils  where  no  trouble 
appeared ;  the  results  are  given  in  previous  reports. 

The  depth  of  four  feet  has  been  adopted  as  the  proper  one,  because 
investigations  in  the  San  Joaquin  Valley  and  in  the  valley  of  southern 
California  have  shown  that  in  all  but  the  sandiest  of  soils  the  substrata 
below  that  depth,  while  not  entirely  free  from  alkali  salts,  contain  so 
little  and  are  so  commonly  beyond  the  depth  to  which  rainfall  or  irri- 
gation water  penetrates  or  the  effect  of  subsequent  surface  evaporation 
is  felt,  that  the  consideration  of  their  content  of  alkali  is  unimportant. 

Field  of  Observation.— The  Tulare  and  Southern  California  substa- 
tions have  thus  far  been  almost  the  only  fields  of  observation,  while 
experiments  on  reclamation  problems  have  been  conducted  at  the  former 
station  at  the  same  time. 

The  Tulare  tract  was  originally  chosen  for  the  purpose  of  making  its 
alkali  land  the  subject  of  special  study  and  investigation ;  and  at  that 
time  but  one  large  alkali  spot  was  in  sight  on  the  surface,  the  rest  being 
covered  with  native  grasses  and  wildflowers.  Alkali  hardpan,  however, 
did  exist  at  depths  of  from  twelve  to  thirty-six  inches,  and  the  necessary 
use  of  irrigation  water  has,  by  percolation  to  the  alkali  and  subsequent 
capillary  rise,  brought  the  dissolved  salts  to  the  surface  here  and  there 
over  the  tract,  and  produced  a  number  of  gradually  enlarging  alkali 
spots.  This  gave  a  larger  field  of  reclamation  work  than  had  been 
intended  at  first,  while  at  the  same  time  enlarging  the  scope  of  obser- 
vation on  various  cultures.     The  effect  of  this  rise  of  alkali  was  seen 


30  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT   STATION. 

in  the  blighted  appearance  of  tree  growths  and  other  cultures  that  had 
at  first  been  doing  well,  as  well  as  in  the  bare  spots  so  characteristic  of 
"black  alkali." 

Reclamation  of  the  black  alkali  has  been  carried  on  for  a  number  of 
years,  gypsum  being  applied,  turned  under  and  thoroughly  watered. 
The  result  has  been  a  very  general  conversion  of  the  dreaded  carbonate 
of  soda  into  the  far  less  harmful  sulfate ;  and  on  spots  where  not  a  blade 
of  grass  would  previously  grow,  there  have  been  produced  excellent 
wheat  and  barley,  three  or  four  feet  high  and  full-headed,  although 
the  surface  of  the  ground  was  at  harvest  time  covered  by  a  thick  crust 
of  white  alkali.     (See  Fig.  5,  page  19.) 

Extent  of  the  Investigation. — About  one  hundred  varieties  of  cultures 
have  been  studied ;  these  embrace  orchard  trees,  grain  and  forage  crops, 
grasses,  vegetables,  and  other  miscellaneous  growths.  The  greater  part 
of  the  results  are  valuable  toward  reaching  the  end  in  view,  but  others 
were  disappointing  in  that  the  soils  showed  a  far  less  amount  of  alkali 
salts  than  was  indicated  by  surrounding  conditions. 

In  many  cases,  several  localities  were  chosen  for  the  examination  of 
the  soil  of  the  same  culture,  for  it  is  impossible  to  judge  of  the  nature 
and  extent  of  alkali  soils  by  the  eye  alone.  For  instance,  many  alfalfa 
fields  in  several  parts  of  the  State  were  sampled  before  conclusions  at 
all  satisfactory  were  reached,  the  majority  having  less  than  we  had 
reason  to  believe. 

The  samples  have  all  been  carefully  taken,  each  foot  of  the  vertical 
soil-column  being  carefully  mixed,  in  order  that  its  sample  may  be  an 
average  of  that  foot.  Many  hundred  analyses  have  been  made  with 
the  assistance  of  Messrs.  Colby,  Snow,  Lea,  and  Werthmueller. 

A  quick  and  at  the  same  time  accurate  method  of  extracting  the 
alkali  from  the  soil  has  been  adopted;  instead  of  placing  the  dry  soil 
on  a  filter  and  washing  all  of  the  alkali  out  with  water,  which  often 
required  two  or  more  weeks  in  clay  soils  because  of  puddling  by  the 
carbonate  of  soda,  a  weighed  amount  is  mixed  with  a  measured  quan- 
tity of  water  and  allowed  to  digest  for  twenty-four  hours  with  frequent 
shaking.  The  salts  thus  dissolved  are  thoroughly  diffused  through  the 
liquid,  and  an  aliquot  part  may  be  taken  for  evaporation  and  examina- 
tion. If  necessary,  a  portion  may  be  passed  through  a  filter  to  clear  it 
from  sediment,  but  very  often  the  solution  settles  perfectly  clear. 

Difficulties  in  Interpretation  of  Results. — There  are  a  number  of  con- 
ditions which  may  affect  the  interpretation  of  the  results  of  alkali 
examinations  and  lead  to  erroneous  conclusions  with  regard  to  the 
effect  of  alkali  on  cultures.  These  are  climatic  conditions,  the  possible 
presence  of  insects  or  diseases,  imperfect  physical  conditions  in  the  soil 
and  subsoil,  such  as  hardpan,  high  water-table,  shallowness  of  the  soil, 


TOLERANCE  OF   ALKALI  BY   GRAIN.  31 

lack  of  ventilation  and  aeration,  poor  moisture  supply,  etc.,  any  of 
which  might  cause  intense  suffering  on  the  part  of  the  plant.  All  of 
these  must  be  considered  before  alkali  can  be  charged  with  the  trouble. 
Then  when  we  come  to  consider  the  alkali  itself  we  are  met  by  its  com- 
plexity and  variability  in  composition,  and  it  is  only  by  a  process  of 
elimination  that  definite  conclusions  can  be  reached.  It  is  easy  enough 
to  make  tables  showing  the  highest  amount  of  each  salt  thus  far  found 
to  be  tolerated  by  the  different  cultures,  but  it  is  often  very  difficult  to 
say  positively  that  the  death  or  suffering  on  the  part  of  a  culture  is  due 
to  the  presence  of  a  certain  salt,  for  other  salts  are  always  present  in 
large  or  small  amounts.  When,  however,  the  amount  of  one  of  the  con- 
stituents is  far  below,  and  that  of  another  is  much  above  the  amount 
tolerated  by  the  plant  elsewhere,  it  is  quite  safe  to  conclude  that  any 
distress  on  the  part  of  the  plant  is  due  to  the  latter;  provided,  of  course, 
that  physical  conditions  of  the  soil  are  favorable  to  the  life  of  the  plant. 
In  some  cases  where  the  amount  of  a  certain  salt  was  enormous,  there 
could  be  but  little  doubt  that  the  suffering  of  the  plant  was  due  to  it ; 
but  the  lowest  limit  of  such  intolerance  is  as  yet  undetermined. 

The  following  tables  give  some  of  the  results  obtained  by  the  analysis 
of  the  alkali  soils  bearing  various  crops,  the  effort  being  to  select  such 
as  were  typical  of  the  effect  and  non-effect  of  alkali  upon  the  growth. 
While  the  samples  were  actually  examined  for  each  foot  in  depth,  it  has 
been  thought  best  for  this  bulletin  to  give  only  the  average  of  the  entire 
column  as  a  whole,  especially  for  the  orchard  trees  whose  roots  penetrate 
deeply  into  the  soil  when  free  to  do  so.  For  smaller  cultures,  whose 
roots  are  chiefly  found  in  the  upper  two  feet  of  the  soil,  we  give  results 
for  each  of  the  two  feet  and  the  total  found  in  four  feet ;  otherwise  the 
results  would  prove  very  puzzling  and  conflicting.  The  results  are 
briefly  discussed  for  each  culture  and  a  comparative  summary  of  maxi- 
mum tolerance  is  given  in  tabular  form  at  the  end  of  the  bulletin. 

We  do  not  present  all  of  the  soils  whose  examinations  have  been 
made,  but  only  those  of  most  importance  in  showing  the  maximum  of 
tolerance  for  the  various  crops;  as  already  stated,  many  alkali  spots 
were  examined  that  gave  no  definite  results,  and  are  therefore  omitted 
from  the  statement. 

It  should  be  said  that  the  limits  of  tolerance  thus  far  shown  are 
probably  too  low  for  many  of  the  cultures  and  that  further  investigation 
will  without  doubt  greatly  enlarge  these  limits  on  the  part  of  some  of 
the  crops  enumerated. 

GRAIN. 

Observations  have  been  made  for  a  number  of  years  on  the  grains  of 
the  experiment  station  at  Tulare,  and  it  has  been  proven  that  they  will 
grow  in  alkali  soils  containing  26,000  pounds  of  salt  per  acre  in  a  depth 


32 


UNIVERSITY    OF   CALIFORNIA EXPERIMENT    STATION. 


of  four  feet  where  there  is  an  absence  of  sufficient  carbonate  of  soda 
to  corrode  the  tender  crowns  of  the  roots. 


Alkali  Salts  in  Grain  Lands. 


Per  Cent  in  Soil. 


Condition. 


Wheat— 

Tulare — Russian 

Plot 


12  j 


Plot  16 


Armona 


Gluten  Wheat- 
Tulare 


Parley — 

Tulare 

Tulare  (  in  2  feet  soil) 

Tulare 

Hynes 


Rye — 

Tulare. 


3  feet  high  . 
20  in.  high  . 
6  in.  high .. 

Good 

Medium  ._. 
Very  poor.. 
Dead ... 


4  feet  high 
Good 


4  feet  high  _. 
Yield  1  ton 

Dead 

Dead 


.064 
.095 
.213 
.089 
.126 
.289 
.144 


.027 
.131 


.063 
.150 
.061 
.076 


.061 


.006 
.009 
.023 
.005 
.001 
.002 
.026 


.019 
.012 


.074 
.028 
.117 
.020 


.006 


007 

.077 

004 

.108 

017 

.253 

007 

.101 

025 

.152 

054 

.345 

034 

.204 

001 

.047 

009 

.152 

015 

.152 

064 

.242 

020 

.198 

056 

.152 

Oil 

.078 

Pounds  per  Acre :  4  ft.  depth. 


CO 


10,240 
15,120 
34,120 
14,160 
20,120 
46,160 
23,040 


4,240 

20,960 


10,720 

12,020 

9,760 

12,160 


9,8011 


1,000 

1,480 

3,640 

720 

200 

360 

4,180 


3,000 

1,880 


12,170 
2,200 

18,720 
3,200 


960 


o 

i! 

,  o 


1,120 
680 
2,680 
1,160 
3,920 
8,680 
5,360 


200 
1,480 


2,630 
5,100 
3,200 
8,960 


1,720 


12,360 
17,280 
40,440 
16,040 
24,240 
55,200 
32,580 


7,440 
24,320 


25,520 
19,320 
31,680 
24,320 


12,480 


Wheat.— The  Russian  wheats,  received  from  the  U.  S.  Department  of 
Agriculture,  were  planted  in  plot  12  of  the  Tulare  substation.  The 
rows  extended  across  an  alkali  spot  and  the  growths  presented  heights 
corresponding  to  the  strength  of  alkali;  that  in  the  soil  of  strongest 
alkali  being  about  six  inches,  that  at  the  end  of  the  rows  where  alkali 
was  weak  having  a  height  of  several  feet.  Samples  of  soil  were  taken 
at  the  two  extremes  and  at  a  medium  point,  as  shown  in  the  table  above. 
The  gradation  in  size  seems  to  follow  a  similar  gradation  in  amount  of 
carbonate  of  soda,  in  inverse  order,  the  smaller  the  carbonate  the  higher 
the  stalk  of  wheat,  1,480  pounds  being  about  the  limit  of  tolerance. 
The  amount  of  common  salt  was  rather  small  to  influence  the  results 
with  the  Russian  wheats,  but  on  plot  16  with  other  varieties  it  seemed 
to  be  the  chief  agent,  the  grain  suffering  more  and  more  as  the  salt 
increased,  a  medium  height  occurring  where  there  was  3,920  pounds 
per  acre  in  four  feet  depth.  The  plot  on  which  this  wheat  was  planted 
is  quite  sandy  and  deep,  with  a  thin  incrustation  of  alkali  on  the 
surface,  especially  where  the  grain  was  poorest. 

On  plot  16,  and  in  fact  on  all  of  the  northwest  corner  of  the  station 
which  is  given  to  wheat,  the  ground  was  covered  with  a  thick  and  white 
crust  of  alkali  salts,  even  where  the  grain  was  several  feet  in  height. 
The  soil  here  is  more  of  a  loamy  nature  than  that  of  plot  12,  and  was 


3     P» 


£*  a 


3— bul.  128-133 


34  UNIVERSITY    OF   CALIFORNIA — EXPERIMENT    STATION. 

once  a  black  alkali  spot  utterly  bare  of  vegetation,  but  has  been 
reclaimed  by  applications  of  gypsum. 

The  sample  from  Armona,  Kings  County,  is  from  land  once  included 
in  Tulare  Lake  region,  but  long  left  dry  by  the  drying-up  of  the  lake. 
Here  the  wheat  died  in  presence  of  4,180  pounds  (.026  per  cent)  of 
carbonate  of  soda  and  5,360  pounds  (.034  per  cent)  of  common  salt 
per  acre  in  four  feet,  each  being  above  the  probable  limits  of  tolerance. 

From  the  results  thus  far  obtained  we  would  judge  that  wheat  should 
do  well  in  deep  and  loose  soils  having  not  more  than  20,000  pounds  of 
total  alkali,  of  which  there  is  not  more  than  1,200  pounds  each  of  car- 
bonate of  soda  and  common  salt  per  acre  in  four  feet  depth. 

Barley. — The  fact  is  shown  in  the  table  that  barley  grew  to  a  height 
of  four  feet  in  land  containing  more  than  12,000  pounds  (.028  per  cent) 
of  carbonate  of  soda  per  acre  in  four  feet,  and  produced  one  ton  of  hay 
per  acre  in  presence  of  more  than  5,000  pounds  (.064  per  cent)  of 
common  salt.  It  is  therefore  better  adapted  to  alkali  land  than  is  wheat. 
It  was  killed  by  18,720  pounds  of  carbonate  of  soda,  as  would  happen 
with  most  plants. 

In  total  salts,  estimating  the  weight  of  the  soil  per  acre-foot  at 
4,000,000  pounds,  we  find  for  the  land  on  which  barley  refused  to  grow 
the  figure  31,680  pounds  of  total  salts  per  acre,  corresponding  to  0.198 
per  cent;  while  for  the  land  on  which  barley  gave  a  full  crop  we  find 
25,520  pounds,  equivalent  to  0.152  per  cent  for  the  whole  soil  column 
of  four  feet.  In  the  other  case,  where  barley  produced  a  ton  per  acre, 
the  percentages  are  higher  (.242  of  total  and  .064  of  common  salt),  but 
the  alkali  was  in  the  upper  two  feet  and  not  distributed  through  four 
feet,  thus  giving  a  smaller  result  when  calculated  in  pounds  per  acre. 

It  thus  appears  that  for  barley  the  limits  of  tolerance  lie  between 
the  above  two  figures,  which  might,  of  course,  have  been  obtained 
equally  well  from  an  average  sample  of  the  4-foot  column  by  making 
a  single  analysis.  It  should  be  noted  that  in  this  case  a  full  crop  of 
barley  was  grown  even  when  the  alkali  consisted  of  fully  one  half  of 
the  noxious  carbonate  of  soda,  proving  that  it  is  not  necessary  in  every 
case  to  neutralize  the  entire  amount  of  that  salt  by  means  of  gypsum, 
which  in  the  present  case  would  have  required  about  9%  tons  of  gypsum 
per  acre— a  prohibitory  expenditure. 

Rye.— A  fair  test  has  not  been  given  to  rye  as  to  its  capabilities  of 
withstanding  alkali  salts,  for  the  amount  found  in  the  soil  in  which  it 
was  growing  at  the  Tulare  substation  was  very  small.  It,  however, 
appears  to  be  about  like  barley  in  its  tolerance  of  alkali  salts. 

LEGUMES. 

Both  the  natural  growth  of  alkali  lands  and  experimental  tests  seem 
to  show  that  this  entire  family  (peas,  beans,  clovers,  etc.)   are  among 


TOLERANCE   OP    ALKALI    BY    LEGUMES.  35 

the  more  sensitive  and  least  available  wherever  black  alkali  exists, 
while  fairly  tolerant  of  the  white  (neutral)  salts.  Apparently  a  very 
little  salsoda  suffices  to  destroy  the  tubercle-forming  organisms  that 
are  so  important  a  medium  of  nitrogen-nutrition  in  these  plants. 
Alfalfa,  with  its  hard,  stout,  and  long  taproot,  seems  to  resist  best  of 
all  these  plants,  excepting  the  melilots.  As  a  general  thing,  taprooted 
plants,  when  once  established,  resist  best,  for  the  obvious  reason  that 
the  main  mass  of  their  feeding  roots  reaches  below  the  danger  level. 
Another  favoring  condition,  already  alluded  to,  is  heavy  foliage  and 
consequent  shading  of  the  ground;  alfalfa  happens  to  combine  both  of 
these  advantages.  There  has  been  some  difficulty  in  obtaining  a  full 
stand  of  alfalfa  in  the  portion  of  the  Chino  tract  containing  from 
4,000  to  6,000  pounds  of  alkali  salts  per  acre;  but  once  obtained  it  has 
done  very  well.  The  only  other  plant  of  this  family  that  succeeds  well 
on  this  land,  and  even  (at  Tulare)  on  soil  considerably  stronger  (prob- 
ably between  20,000  and  30,000  pounds),  are  the  two  melilots,  M.  indica 
and  alba;  the  latter  (the  Bokhara  clover)  is  a  forage  plant  of  no  mean 
value  in  moist  climates,  but  somewhat  restricted  in  its  use  in  California 
because  of  the  very  high  aroma  it  develops,  especially  in  alkali  lands; 
so  that  stock  will  eat  only  limited  amounts,  best  when  intermixed  with 
other  forage,  such  as  the  saltbushes.  The  yellow  melilot  is  highly 
recommended  by  the  Arizona  station  as  a  greenmanure  plant  for  winter 
growth;  but  in  this  State  it  is  a  summer-growing  plant  only,  and  is 
refused  by  stock.  Very  few  plants  belonging  to  this  family  are  naturally 
found  on  alkali  lands,  and  attempts  to  grow  them,  even  where  only 
glauber  salt  is  present,  have  been  but  very  moderately  successful.  The 
salts  seem  to  retard  or  even  prevent  the  formation  of  the  tubercles 
useful  for  nitrogen  absorption;  and  for  most  of  the  legumes  the  limit 
of  full  success  seems  to  lie  between  3,000  and  4,000  pounds  to  the  acre. 

Alfalfa. — Young  alfalfa  roots  are  very  tender  and  sensitive  to  the 
corrosive  action  of  carbonate  of  soda,  and  being  confined  to  the  upper- 
foot  or  two  of  the  soil  are  fully  within  its  reach.  But  when  the  roots 
are  older  and  have  penetrated  deeply  into  the  soil,  the  root-crown  has 
become  more  corky  and  hardened  and  less  sensitive,  so  that  they  are 
enabled  to  withstand  a  far  larger  amount  of  the  alkali. 

From  the  many  observations  made  at  the  substations  and  elsewhere 
we  may  place  the  tolerance  of  young  alfalfa  at  about  .015  per  cent  of 
carbonate  of  soda,  .009  per  cent  of  common  salt,  and  .150  per  cent  of 
sulfate  of  soda  in  the  upper  two  feet  of  soil ;  this  is  equivalent  to  1,200 
pounds  of  carbonate,  750  pounds  of  common  salt,  and  12,000  pounds 
of  sulfate  per  acre  in  two  feet.  Old  alfalfa  did  well  in  twice  these 
amounts  in  the  upper  two  feet. 

The  tolerance  of  alfalfa  after  a  good  growth  is  secured  may  be  placed 


Carbon- 

Common 

Total 

ate. 

Salt. 

Alkali. 

720 

175,840 

236,680 

-._ 

1,040 

18,640 

36  UNIVERSITY    OF   CALIFORNIA — EXPERIMENT   STATION. 

at  more  than  2,000  pounds  of  carbonate  of  soda,  5,000  pounds  of 
common  salt,  and  75,000  pounds  of  sulfate  of  soda  per  acre  in  four  feet 
depth. 

It  is  therefore  very  essential  that  prior  to  sowing  alfalfa  the  alkali 
salts  should  be  leached  downward  from  the  surface  by  thorough  irri- 
gation, until  the  plant  is  old  enough  to  resist  their  attack  by  the 
hardening  of  its  root-crown. 

The  importance  of  thoroughly  washing  the  alkali  deeply  into  the  soil 
before  the  seed  is  planted,  and  keeping  it  there  by  proper  means  until 
the  foliage  of  the  plant  shades  the  soil  sufficiently  to  prevent  the  rise  of 
moisture  and  alkali,  is  well  illustrated  in  fields  in  the  region  of  Bakers- 
field,  where  alfalfa  is  now  growing  in  soils  once  heavily  charged  with 
alkali.  From  one  of  these  fields  samples  of  soil  were  taken  by  us  where 
the  alkali  was  supposed  to  be  strongest  beneath  the  alfalfa,  and  also 
from  an  adjoining  untreated  bare  alkali  spot  which  was  said  to  represent 
conditions  before  alfalfa  was  planted.  The  results  are  given  in  pounds 
per  acre  in  four  feet  depth : 

Sulfates. 

Alkali  spot  before  alfalfa  was  planted...  60,120 
Alfalfa  field:  alkali  washed  down 14,400 

In  the  natural  alkali  soil  the  salts  are  distributed  downward,  some- 
what evenly,  except  that  there  is  in  the  surface  foot  nearly  140,000 
pounds  of  common  salt,  while  in  the  alfalfa  field  the  alkali  salts  are 
chiefly  below  the  second  foot.  A  closer  examination  would  doubtless 
have  shown  the  main  body  of  alkali  to  have  been  washed  down  to  six 
feet  from  the  surface,  or  even  deeper. 

Blue  European  Lupin.— The  plot  in  which  the  lupins  were  grown  has 
the  greater  part  of  its  alkali  within  the  upper  two  feet,  while  in  that 
part  where  the  lupins  failed  three-fourths  of  the  common  salt  and  the 
sulfates  was  held  in  the  first  foot  itself.  Both  the  common  salt  and 
sulfates  seem  to  be  responsible  for  the  failure  of  the  lupins,  and  it  is 
clear  that  it  can  not  withstand  more  than  5,000  pounds  (.025  per  cent) 
of  the  former  per  acre ;  of  the  carbonate  of  soda  it  will  tolerate  as  much 
as  and  perhaps  more  than  3,000  pounds  (.018  per  cent)  per  acre. 

Hairy  Vetch.— This  fodder  and  greenmanuring  plant  grew  fairly 
well,  reaching  a  height  of  about  14  inches  and  bloomed  in  land  con- 
taining 2,400  pounds  (.016  per  cent)  of  carbonate  of  soda,  3,160  pounds 
(.020  per  cent)  of  common  salt,  and  63,700  pounds  (.398  per  cent)  of 
sulfate  per  acre  in  four  feet  depth.  As  with  the  lupins  and  the  vege- 
tables, we  find  that  here,  too,  the  alkali  occurs  chiefly  in  the  upper  two 
feet  of  the  soil,  the  common  salt  especially  being  in  the  first  foot. 

The  very  large  amount  of  sulfates  tolerated  would  show  that  when 


TOLERANCE  OP  ALKALI  BY  FODDER  PLANTS. 


37 


black  alkali  lands  are  neutralized  with  gypsum,  the  vetch  will  do  fairly 
well,  provided  that  common  salt  is  not  excessive.  The  limit  of  toler- 
ance of  the  latter  is  a  matter  of  doubt,  for  in  the  soil  in  which  the  vetch 
had  a  poor  growth,  there  was  present  about  4,000  pounds  (.025  per  cent) 
of  carbonate  in  addition  to  the  7,480  pounds  (.047  per  cent)  of  chlorid, 
and  to  either  of  these  salts  may  have  been  due  the  bad  effect.  But  in 
both  of  the  soils  examined  the  carbonate  was  chiefly  in  the  second  and 
third  feet,  and  as  its  action  is  chiefly  upon  the  tender  root-crown  at 
the  surface  of  the  soil,  it  would  seem  that  the  common  salt  was 
responsible  for  poor  growth. 

Bur  Clover.— This  clover  was  found  growing  luxuriantly  in  a  small 
field  adjoining  the  hot  sulphur  baths  at  Elsinore,  in  Riverside  County. 
The  soil  received  its  water  from  a  deep  well,  and  was  black  from 
humus  dissolved  in  the  carbonate  of  soda  of  the  alkali.  An  exam- 
ination of  the  soil  to  thirty  inches  depth  showed  the  remarkable  toler- 
ation of  11,300  pounds  (.113  per  cent)  of  carbonate  of  soda  per  acre, 
thus  giving  it  the  rank  of  second  in  this  regard  among  all  the  cultures 
examined.  It  doubtless  is  fully  as  tolerant  as  barley,  which,  aside  from 
sorghum,  heads  the  tolerance  list  of  grasses  thus  far. 

Fenugreek  and  Crimson  Clover.— In  the  station  at  Chino  these  were 
killed  in  a  soil  having  1,520  pounds  of  sulfate  of  soda  and  1,440  pounds 
of  carbonate  of  soda  (.012  per  cent)  per  acre  in  three  feet  depth. 

Sweet  Peas.— In  the  region  of  Ross,  Marin  County,  sweet  peas  died 
in  a  soil  containing  .037  per  cent  of  common  salt  in  the  first  foot.  This 
is  equivalent  to  nearly  1,500  pounds  per  acre. 

OTHER   FODDER   PLANTS. 

Australian  Saltbush  (Atriplex  semibaccata)  .—This  plant  has  been 
found  growing  well  in  very  strong  alkali  land,  in  which  the  several 
salts  were  in  greatest  amount  within  two  feet  of  the  surface.  As  it 
ranks  high  as  a  fodder  plant  suitable  for  alkali  soils,  we  give  the  distri- 
bution of  the  salts  in  the  soil-column: 


Alkali  Soil  Growing  Australian  Saltbush 

. 

per  Acre. 

Percentage  in  Soil. 

Pounds 

Depth. 

op             o 

t^                              ''I 

£          8" 

CO                             jS 
!                             CD 

o 
fcj; 
o 

►a 

o 

CO 

a 

CD 
00 

o 

f» 

o 
B 

CD 

o 

PI 

■ 

Hi 

o 
g 

Firstfoot 

Second  foot ..     . 

2.055 
.634 
.247 
.205 

.284 
.089 
.042 
.049 

.121 
.111 
.051 
.030 

2.460 
.834 
.340 

.284 

82,200 

25,360 

9,880 

8,200 

11,360 
3,560 
1,680 
1,960 

4,840 
4,440 
2,040 
1,200 

98,40C 
33.360 
13,600 
11,360 

Third  foot . . . 

Fourth  foot . 

Total 

3.141 

.464 

.313 

3.918 

125,640 

18,560 

12,520 

156,720 

38  UNIVERSITY    OF   CALIFORNIA  — EXPERIMENT    STATION. 

These  figures  doubtless  very  nearly  represent  the  maximum  tolerance 
of  the  saltbush. 

Very  young  plants  have,  however,  suffered  or  languished  in  surface 
soils  containing  9,000  pounds  (.056  per  cent)  of  carbonate  of  soda  and 
11,000  pounds  (.070  per  cent)  of  common  salt,  or  a  total  of  31,000 
pounds  of  alkali  salts  per  acre;  and  have  died  when  the  soil  was  covered 
with  an  alkali  crust  containing  4.0  per  cent  of  carbonate  and  6.0  per 
cent  of  common  salt.  The  plant  came  up  easily  from  the  seed  in  a  soil 
containing  5,000  pounds  (.032  per  cent)  of  carbonate  of  soda  and 
3,000  pounds  (.019  per  cent)  of  common  salt  per  acre. 

Sorghum.— At  the  Tulare  substation  sorghum  grows  luxuriantly  in  a 
small  tract  having  a  large  amount  of  alkali,  the  surface  often  being 
black  from  humus  held  by  the  carbonate  of  soda.  Irrigation  is  used  on 
the  crop,  and  there  is  therefore  more  alkali  at  the  surface  than  at  the 
third  and  fourth  feet,  although  the  dense  mass  of  the  crop  shades  the 
soil  quite  effectually.  An  examination  of  the  soil  shows  a  higher  amount 
of  alkali  salts  than  in  the  soil  of  any  small  culture  thus  far  examined, 
viz. :  81,440  pounds  per  acre  in  four  feet  depth.  This  is  more  than 
one  half  of  one  per  cent.  Sorghum  can  easily  tolerate  as  much  as  10,000 
pounds  (.062  per  cent)  of  carbonate  of  soda,  the  same  of  common  salt, 
and  65,000  pounds  (.40  per  cent)  of  glauber  salt  per  acre  in  four  feet. 
At  the  time  the  examination  was  made,  one  half  of  the  total  glauber 
salt  was  in  the  upper  foot,  the  greater  part  of  the  carbonate  in  the 
second  and  third  feet,  while  the  common  salt  was  quite  evenly  dis- 
tributed through  the  four  feet. 

ROOT  CROPS  AND  VEGETABLES. 

It  seems  to  be  generally  true  that  root  crops  suffer  in  quality,  how- 
ever satisfactory  may  be  the  quantity  harvested  on  lands  rich  in  salts, 
and  especially  in  chlorids  (common  salt).  It  was  noted  at  the  Tulare 
substation  that  the  tubers  of  the  artichoke  were  inclined  to  be 
"squashy"  in  the  stronger  alkali  land,  and  failed  to  keep  well;  the 
same  was  true  of  potatoes,  which  were  very  waterj^ ;  and  also  of  turnips 
and  carrots.  It  is  a  fact  well  known  in  Europe,  that  potatoes  manured 
with  kainit  (chlorids  of  potassium  and  sodium)  are  unfit  for  the  manu- 
facture of  starch,  and  are  generally  of  inferior  quality.  But  this  is 
found  not  to  be  the  case  when,  instead  of  the  chlorids,  the  sulfate  is 
used;  hence  the  advice,  often  repeated  by  this  Station,  that  farmers 
desiring  to  use  potash  fertilizers  should  call  for  the  "high-grade  sul- 
fate" instead  of  the  cheaper  kainit,  which  adds  to  the  injurious  salts 
already  so  commonly  present  in  California  lowland  soils. 

Sugar  Beets.— The  common  beet  (including  the  mangel-wurzel)  is 
known  to  succeed  well  on  saline  seashore  lands,  and  it  maintains  its 


TOLERANCE  OP  ALKALI  BY  ROOT  CROPS. 


39 


reputation  on  alkali  lands  also.  Being  specially  tolerant  of  common 
salt,  it  may  be  grown  where  other  crops  fail  on  this  account ;  but  the 
roots  so  grown  are  strongly  charged  with  common  salt,  and  have,  as  is 
well  known,  been  used  for  the  purpose  of  removing  excess  of  the  same 
from  marsh  lands.    Such  roots  are  wholly  unfit  for  sugar-making. 

It  is  quite  otherwise  with  glauber  salt  (sodium  sulfate)  ;  and  as  this 
is  usually  predominant  in  alkali  lands,  either  before  or  after  the 
gypsum  treatment,  this  fact  is  of  great  importance,  for  it  permits  of  the 
successful  growing  of  the  sugar  beet;  as  has  been  abundantly  proved  at 
the  Chino  ranch,  where  land  containing  as  much  as  12,000  pounds  of 
salts,  mostly  this  compound,  has  yielded  roots  of  very  high  grade  both 
as  to  sugar  percentage  and  purity. 

The  maximum  of  each  salt  tolerated  by  beets  of  good  sugar  and 
purity  at  Tulare  and  Oxnard  (Station  Bui.  169)  is  shown  in  the  follow- 
ing table : 


Percentage  in  Si.il. 

Pounds  per  Acre. 

Depth. 

go 
p 

cd 

a 

P 

& 

O 
3 
P 

CD 

§ 

o 
Si 

o 
p 
> 
P 

CO 

p 
© 

o 

P 

c- 
o 

P 

o 
o 

>s 
pi 

o 
P 
► 

p 

Tulare — 
Firstfoot 

.752 
.337 

.531 
.304 

.003 
.042 

.028 
.009 

.756 
.388 

29,000 
13,480 

120 

1,680 

1,120 
360 

30,240 

Second  foot 

15,520 

Total  in  2  feet 

Total  in  4  feet 

.022 
.025 

.019 
.0L2 

.572 
.341 

42,480 
48,560 

1,800 
4,000 

1,480 
1,920 

45,760 
54,480 

Oxnard— 
First  foot 

.1980 
.0269 
.0196 

.0084 
.0041 
.0034 

.1120 
.0930 
.0930 

.3184 
.1240 
.1160 

7,920 
1,080 

780 

9,000 
9,780 

320 
160 
120 

480 
600 

4,480 
3,720 
3,720 

12,720 

Second  foot 

Third  foot 

4,960 
4,620 

Total  in  2  feet 

Total  in  3  feet 

.1124 
.0815 

.0062 
.0053 

.1025 
.0993 

.2211 
.1861 

8,200 
11,920 

17,680 
22,300 

It  would  seem,  then,  that  in  the  absence  of  carbonate  of  soda,  sugar 
beets  will  tolerate  as  much  as  8,000  pounds  of  common  salt  per  acre 
in  two  feet  depth.  In  Europe  .25  per  cent  per  foot  (10,000  pounds 
per  acre)  is  considered  the  extreme  limit  in  which  workable  beets  can 
be  obtained,  and  .20  per  cent,  or  8,000  pounds,  is  quite  unobjectionable. 

Carrots.— In  the  tule  marshes  of  the  Sacramento  River  at  Rio  Vista, 
Solano  County,  carrots  are  said  to  have  grown  well  on  a  soil  which  was 
found  to  contain  .139  per  cent  (11,120  pounds  per  acre)  of  common 
salt  in  the  upper  two  feet,  while  in  another  spot  of  good  carrots  there 
was  .260  per  cent  of  common  salt  in  the  upper  foot,  which  is  equivalent 
to  10,400  pounds  per  acre.  There  was  no  carbonate  of  soda  in  either 
soil. 


40 


UNIVERSITY    OF   CALIFORNIA EXPERIMENT    STATION. 


At  the  Tulare  substation,  in  a  plot  having  .223  per  cent  of  sulfates 
(17,800  pounds  per  acre),  .012  of  carbonate  of  soda  (960  pounds  per 
acre),  and  .020  of  common  salt  (1,560  pounds  per  acre)  the  plant  grew 
well  and  its  tubers  had  a  length  of  about  ten  inches,  but  they  had  a 
diameter  of  only  about  three  fourths  of  an  inch. 

Potatoes.— In  the  reclaimed  tule-marsh  lands  of  Victoria  Island,  in 
the  region  of  Stockton,  potatoes  form  a  prominent  crop,  and  examination 
of  the  soils  shows  that  the  crop  can  tolerate  a  large  amount  of  common 
salt,  as  shown  in  this  table : 


Percentage  in  Soil 

Pounds  per  Acre. 

Depth. 

CO 

CD 
re 

o 
■1 

o 

3 
P 

a 

O 
tr 

o 
pi 

CO 

6? 

CD 

re 

o 

COO 

S  3 

i    a 

o 
cog 

rB 

. .    o 

Firstfoot 

2.013 
.566 
.268 
.406 

.285 
.074 
.148 
.074 

2.298 
.640 
.416 

.480 

20,130 
5,660 
2,680 
4,060 

None. 

2,850 
740 

1,480 
740 

22,980 

Second  foot 

Third  foot  . . 

6,400 
4,160 

Fourth  foot 

4,800 

Total 

.813 



.145 

.958 

32,530 

5,810 

38,340 

The  maximum  of  common  salt  in  the  upper  three  feet  was  .169  per 
cent,  or  an  average  of  5,000  pounds  per  acre.  In  the  fourth  foot  there 
was  an  additional  740  pounds,  making  a  total  of  about  5,800  pounds  in 
the  four  feet.  The  effect  of  so  much  common  salt  on  the  starch  of  the 
potato  has  not  been  ascertained  in  California,  but  is  elsewhere  under- 
stood to  be  unfavorable. 

Onions.— Onions  also  do  well  on  the  reclaimed  tule-marshes,  even  in 
the  presence  of  as  much  as  3,000  pounds  of  common  salt  in  the  upper 
foot  of  soil,  as  was  noted  in  the  land  around  Rio  Vista  and  on  Victoria 
Island.    They  would  tolerate  doubtless  much  more  than  this. 

Celery.— The  celery  fields  in  the  alluvial  lands  around  Santa  Ana 
furnish  good  examples  of  the  effects  of  alkali  salts,  except  that  no  carbon- 
ate of  soda  was  found  in  the  samples  kindly  sent  by  Mr.  Cole  from  spots 
where  the  plant  was  growing  well  and  where  the  plant  died.  The 
results  show  that  celery  will  easily  tolerate  as  much  as  10,000  pounds 
of  common  salt  per  acre,  but  is  killed  by  30,000  pounds.  It  is  killed  by 
2,000  pounds  of  carbonate  of  soda. 

Spinach  and  English  Broad  Bean.— The  vegetables  were  grown 
at  Tulare  on  very  strong  alkali  soils  and  were  almost  complete  failures. 
A  few  scattering  plants  appeared  where  the  carbonate  of  soda  was  only 
2.000  pounds  per  acre  and  chiefly  below  the  first  foot,  but  they  reached 


TOLERANCE  OF  ALKALI  BY  GRASSES,  ETC.  41 

a  height  of  only  a  few  inches.    The  amount  of  common  salt  was  about 
9,000  pounds  per  acre. 

Asparagus  is  another  crop  which  bears  considerable  amounts  of  com- 
mon salt  as  well  as  of  glauber  salt ;  but  not  of  salsoda,  which  must  first 
be  transformed  by  the  use  of  gypsum. 

Rhubarb  was  a  conspicuous  failure  in  even  the  weak  alkali  lands  of 
the  Chino  tract. 

GRASSES,  TEXTILE  PLANTS,  AND  WEEDS. 

brasses.— Summarizing  the  data  given  in  former  publications  we  have 
the  following  groupings  of  maximum  amounts  in  the  surface  foot  per 
acre  in  which  the  true  grasses  have  thus  far  been  found  to  do  well : 

Grasses  Growing  in  Alkali  Soils.     Depth  one  foot. 

Carbonate  of  Soda. 
3,300  lbs.  per  acre:  Japanese  Wheat  Grass,  Barley. 
2,500  to  3,000  lbs.  per  acre:  Awnless  Brome    Grass,   Schrader's    Brome    Grass,   Sheep 

Fescue,  Tall  Fescue. 
2,000  to  2,500  lbs.  per  acre:  Egyptian  Millet,  Hard  Fescue,  Many-Flowered  Paspalum, 

English  Ray  Grass,  Rough-Stalked  Meadow  and  Orchard 
Grass. 
1,000  to  2,000  lbs.  per  acre:  Bearded  Darnel,  Blue  Grass,  Foxtail,  and  Alfileria. 
600  to  1,000  lbs.  per  acre:  Meadow    Fescue,   Many-Flowered    Millet,    Meadow    Soft 
Grass,  Italian  Ray  Grass. 

Common  Salt. 
7,040  lbs.  per  acre:  Barley. 

3,000  lbs.  per  acre:  Japanese  Wheat  Grass,  Foxtail,  and  Alfileria. 
1,500  lbs.  per  acre:  Schrader's  Brome  Grass. 
900  lbs.  per  acre:  Awnless  Brome  Grass,  Sheep  Fescue,  Tall  Fescue. 
250  to  500  lbs.  per  acre:  Many-Flowered  Millet,  Italian  Ray   Grass,  English  Ray- 
Grass,  Bearded  Darnel,  Orchard  Grass. 

Textile  Plants.— Japanese  hemp  seemed  to  have  a  hard  struggle 
with  the  alkali  while  young,  but  at  the  end  of  the  season  stood  eight 
feet  high.  The  ramie  plant,  also,  will  bear  moderately  strong  alkali, 
apparently  somewhat  over  12,000  pounds  per  acre.  Flax  has  not  been 
tested  in  cultivation;  but  its  wide  distribution  all  over  the  States  of 
Oregon  and  Washington  would  seem  to  indicate  that  it  is  not  very 
sensitive.  Another  textile  plant,  the  Indian  mallow  (Abutilon 
avicennae),  was  found  to  fail  on  the  Chino  alkali  soil. 

Weeds. — Like  the  legumes,  wild  plants  of  the  mustard  family  are 
rare  on  alkali  lands ;  and  correspondingly,  the  cultivated  mustard,  kale, 
rape,  etc.,  fail  even  on  land  quite  weak  in  alkali.  Their  limit  of  toler- 
ance seems  to  lie  near  4,000  to  5,000  pounds  per  acre  of  even  white  salts. 

Several  of  the  hardiest  of  the  native  "alkali  weeds"  belong  to  the 
sunflower  family,  and  the  common  wild  sunflowers  (Helianthus  calif  or- 
nicus  and  H.  annuus)  are  common  on  lands  pretty  strongly  alkaline. 


42  UNIVERSITY    OF   CALIFORNIA —  EXPERIMENT   STATION. 

Correspondingly,  the  "Jerusalem  artichoke,"  itself  a  sunflower,  is 
among  the  available  crops  on  moderately  strong  alkali  soils;  and  so, 
doubtless,  are  other  members  of  the  same  relationship  not  yet  tested, 
such  as  the  true  artichoke,  salsify,  etc.  Chicory,  belonging  to  the  same 
family,  yielded  roots  at  the  rate  of  12  tons  per  acre,  on  land  on  the 
Chino  tract  containing  about  8,000  pounds  of  salts  per  acre. 

GRAPEVINES. 

The  Vitis  vinifera  is  quite  tolerant  of  white  or  neutral  alkali  salts, 
and  will  resist  even  a  moderate  amount  of  the  black  so  long  as  no  hard- 
pan  is  allowed  to  form.  At  the  Tulare  substation  in  1899  it  was  found 
that  grapevines  did  well  in  sandy  land  containing  35,230  pounds 
(.220  per  cent)  of  alkali  salts  per  acre  in  four  feet  depth,  of  which  one 
half  was  glauber  salt,  9,640  pounds  carbonate  of  soda,  7,550  pounds 
common  salt,  and  750  pounds  nitrate  of  soda.  They  were  badly  dis- 
tressed where,  of  a  total  of  37,020  pounds  (.282  per  cent)  of  alkali 
salts,  25,620  pounds  (.160  per  cent)  was  carbonate  of  soda;  while  where 
the  vines  had  died  out,  there  was  found  a  total  of  73,930  pounds  (.412 
per  cent),  with  37,280  pounds  (.233  per  cent)  of  carbonate  in  a  depth 
of  four  feet.  The  European  vine,  then,  is  considerably  more  resistant 
of  alkali,  even  in  its  worst  (black)  form,  than  barley  and  rye;  and  it 
seems  likely  that  the  native  grapevines  of  the  Pacific  Coast,  Calif ornica 
and  Arizonica,  would  resist  even  better ;  a  point  still  under  experiment. 

Experience,  however,  has  shown  that  vines  rapidly  succumb  when  by 
excessive  irrigation  the  bottom  water  is  allowed  to  rise,  increasing  the 
amount  of  alkali  salts  near  the  surface  and  shallowing  the  soil  at  their 
disposal.  Such  over-irrigation  has  been  a  fruitful  cause  of  injury  to 
vineyards  in  the  Fresno  region,  and  would  doubtless,  if  practiced,  kill 
most  of  the  vines  at  Tulare  substation  which  are  now  flourishing.  In 
such  cases  sometimes  the  formation  of  hardpan  is  followed  by  that  of  a 
concentrated  alkaline  solution  above  it,  strong  enough  to  corrode  the 
roots  themselves,  and  not  only  killing  the  vines,  but  rendering  the  land 
unfit  for  any  agricultural  use  whatsoever.  The  swamping  of  alkali 
lands,  whether  of  the  white  or  black  kind,  is  not  only  fatal  to  their 
present  productiveness,  but,  on  account  of  the  strong  chemical  action 
thus  induced,  greatly  jeopardizes  their  future  usefulness.  Many  costly 
investments  in  orchards  and  vineyards  have  thus  been  rendered  unpro- 
ductive, or  have  even  become  a  total  loss. 

Grape  Varieties.— A  large  part  of  the  Tulare  substation  tract  is 
occupied  by  grapes  representing  about  one  hundred  and  fifty  varieties. 
Alkali  spots  have  appeared  here  and  there  (by  rise  from  below  through 
use  of  irrigation  water) ,  and  in  several  instances  the  salts  have  seriously 
affected  the  vines.  The  results  of  the  examination  of  the  soils  forcibly 
illustrate  the  fact  that  the  susceptibility  of  the  vine  varies  according 


TOLERANCE    OF   ALKALI   BY    QRArEVINES. 


43 


to  variety,  and  that  while  some  are  tolerant  of  very  large  amounts 
of  carbonate  of  soda  and  common  salt,  others  succumb  to  the  effect  of 
far  less  of  each. 

Alkali  in  Vineyard  Soils. 


Grapevines. 


Persian.-. 

Persian 

Persian (3  feet 

Sauvignon  vert 

Chasselas . 

Boal  de  Madeira 

Mission  Grape 

Mission  Grape 

Trousseau 

Verdal  

Teinturier  male 

Thompson  Seedless 

Burger 

Meunier 

Meunier "._. 

Meunier 

Flame  Tokay 

Pedro  Jimenes 

Pedro  Jimenes 

Negro 

Negro _ 


Percentage  in  Soil. 

Pound 

s  per  Acre:  4  ft. 

OQ 

o 

o 

H 

02 

o 

a 

Condition. 

£ 

SB 

C3- 

o 

P> 

^ix 

pa 

CD 

1 

SB 

0> 

O 

P 

en  3 

O  ?0 

©go. 

;   o 

*-* 

i  ^ 

Lived  

.144 

.063 

.077 

.284 

17,290 

7,550 

9,640 

Barely  lived 

.072 

.214 

.005 

.291 

8,670 

25,620 

640 

Died  ... 

.205 

.311 

.091 

.607 

24,640 

37,280 

10,890 

Thrifty 

.255 

.003 

.028 

.286 

40.8U0 

480 

4,480 

Thrifty 

.247 

.005 

.031 

.283 

39,520 

800 

4,960 

Thrifty    .... 

.188 

.004 

.028 

.220 

30,080 

640 

3,680 

Thrifty 

.160 

.030 

.006 

.196 

25,610 

4,760 

960 

Not  growing 

.416 

.010 

.006 

.432 

66,520 

1,560 

920 

Thrifty 

.170 

.007 

019 

.196 

27,200 

1,120 

3,040 

Thrifty 

.160 

.003 

.023 

.186 

25,600 

480 

3,680 

Thrifty 

.150 

.003 

.029 

.182 

24,000 

480 

4,640 

Thrifty 

.134 

.003 

.013 

.150 

21,480 

520 

2,040 

Thrifty 

.120 

.005 

.090 

.215 

19,200 

800 

1,440 

Thrifty 

.094 

.010 

.006 

.110 

15,040 

1,600 

960 

Suffered 

.209 

.007 

.012 

.228 

33,440 

1,120 

1,920 

Died 

.207 

.007 

.018 

.232 

33,120 

1,120 

2,880 

Thrifty 

.070 

.045 

.004 

.119 

11,200 

5,560 

600 

Thrifty 

.067 

.023 

.004 

.094 

10,680 

3,600 

600 

Not  growing 

.110 

.029 

.006 

.145 

17,600 

4,640 

960 

Thrifty 

.081 

.012 

.093 

12,960 

1,920 

Not  growing 

.206 

.022 

.005 

.233 

33,000 

3,480 

800 

34,480 
34,930 
72,810 
45,760 
45,280 
34,400 
31,360 
69,000 
31,360 
29,760 
29,120 
24,040 
21,440 
17,600 
36,480 
37,120 
17,360 
14,880 
23,200 
14,880 
37,280 


Of  the  above  fourteen  varieties  of  grapes  the  Persian  withstands  the 
effects  of  alkali  the  best,  especially  of  carbonate  of  soda  and  common 
salt.  There  seems  but  little  doubt  that  it  would  nourish  in  soils  contain- 
ing one  tenth  of  one  per  cent  of  common  salt,  or  an  equivalent  of  16,000 
pounds  per  acre  in  four  feet.  The  tolerance  for  carbonate  of  soda  is 
great,  for  in  the  presence  of  more  than  two  tenths  of  one  per  cent,  or 
25,600  pounds  per  acre,  it  managed  to  keep  alive,  thus  indicating  a 
true  tolerance  of  probably  15,000  or  perhaps  20,000  pounds  per  acre 
in  four  feet. 

For  other  varieties  the  limits  vary  greatly,  some  being  more  sensitive 
to  the  several  salts  than  others.  The  Sauvignon  vert  and  Chasselas 
appear  to  be  more  tolerant  of  glauber  salt  and  common  salt  than  were 
other  varieties,  for  they  made  a  fine  growth  in  the  presence  of  about 
40,000  pounds  of  sulfate  and  5,000  pounds  of  common  salt  per  acre  in 
four  feet.  The  Teinturier  male  would  probably  be  their  equal,  for  its 
amount  of  common  salt  was  nearly  the  same. 

The  amount  of  carbonate  of  soda  (black  alkali)  which  the  grape  is 
able  to  withstand  was  in  a  few  cases  fairly  well  shown,  especially  where 
the  common  salt  was  low.  Thus  the  Flame  Tokay  grew  well  in  soil  with 
5,500  pounds  of  carbonate,  and  the  Mission  in  the  presence  of  4,700 
pounds. 


44 


UNIVERSITY    OF    CALIFORNIA — EXPERIMENT   STATION. 


The  Meunier  is  very  sensitive  to  alkali  salts  and  succumbed  to  small 
amounts  of  carbonate  and  common  salt  combined  with  33,000  pounds 
of  sulfate,  which  was  less  than  that  in  which  many  other  varieties  grew 
well.  As  a  rule,  grapevines  seem  to  easily  withstand  30,000  pounds  of 
sulfate,  and  5,000  pounds  of  carbonate  and  common  salt  each. 


Note  on  the  Effect  of  Alkali  Salts  upon  the  Gkowth  of  Grapevines  and 
on  the  Composition  of  Grapes. 

By  A.  M.  dal  Piaz. 

The  injurious  effect  of  strong  alkali  salts  upon  fruits  in  general  is 
well  known;  grapevines  are  no  exception,  for  strong  alkali  will  kill 
them  and  weaker  alkali  affects  them  proportional  to  its  strength  and 
composition.  The  effect  of  alkali  upon  the  vine  and  its  product  is  a 
matter  of  economic  interest,  and  an  investigation  on  this  subject  was 
begun  by  the  writer  upon  vines  at  the  Tulare  substation  in  1900,  and 
the  results  are  here  briefly  presented;  analyses  of  the  alkali  soils  in 
which  the  vines  were  growing  were  made  in  the  Station  laboratory  by 
Mr.  Snow. 

The  vines  of  the  Burger,  Sauvignon  vert,  and  Trousseau  were  growing 
partly  in  weak  and  partly  in  strong  alkali  soils.  The  grapes  of  each 
variety  did  not  show  any  marked  difference  in  size,  excepting  where 
growing  in  strong  alkali;  but  the  vines  themselves  were  there  con- 
siderably shorter  in  growth,  and  therefore  the  bunches  and  berries  were 
smaller  and  more  advanced  in  maturity. 

The  Meunier  is  growing  about  an  alkali  spot,  partly  on  weak  alkali 
and  showing  a  healthy  growth,  partly  on  stronger  alkali  and  showing  a 
shorter  growth,  and  were  killed  on  still  stronger  alkali.  The  following 
table  gives  the  composition  of  these  alkali  soils,  to  which  is  added  the 
results  of  examination  of  the  sugar,  acid,  ash,  and  tannin  in  the  grapes 
grown  respectively  on  the  weak  and  the  strong  alkali : 

Pounds  of  Alkali  Salts  per  Acre  in  Four  Feet  Depth. 


Sauvignon  Vert. 

Burger. 

Trousseau. 

Meunier. 

Weak 
Alkali. 

Strong 
Alkali. 

Weak 

Alkali. 

Strong 
Alkali. 

Weak 
Alkali. 

Strong 
Alkali. 

Weak 
Alkali. 

Strong 
Alkali. 

Strong 
Alkali. 

Sulfates  

Carbonate 

Chlorid 

21,760 
1,280 
4,480 

25,520 

40,800 

480 

4,480 

19,200 

800 

1,440 

21,280 

640 

1,440 

20,480 

480 

4,000 

27,200 
1,120 
3,040 

15,040 

1,600 

960 

33,440 
1,120 
1,920 

33,120 
1,120 

2,880 

Total 

45,760 

21,440 

23,360 

24,960 

31,360 

17,600 

36,480 

37,120 

Proximate  Composition  of  Grapes:  August  24,  1900. 


Sugar  %. . 
Acid%.._ 
Ash  %  ... 
Tannin  % 


26.39 
.38 

.28 


24.43 
.65 

.37 


20.24 
.71 
.33 


20.60 
.59 
.33 


25.75 

.47 
.49 
.147 


24.64 
.50 


155 


26.86 
.45 
.36 
.159 


24.53 
.50 
.40 
.167 


Vines 
killed. 


TOLERANCE  OP  ALKALI  BY  ORCHARD   CROPS.  45 

The  four  grape  varieties  of  the  above  table,  grown  on  weak  and  strong 
alkali  soils,  show  differences  in  growth  and  grape  composition  remark- 
ably well.  The  sugar  content  seems  to  have  throughout  the  tendency 
of  decreasing  with  increasing  strength  of  the  alkali  salts ;  this  is  shown 
by  the  varieties  of  Sauvignon  vert,  Trousseau,  and  Meunier.  The 
Burger  does  riot  show  this,  because  of  the  nearly  equal  strength  of  alkali 
in  both  soils. 

The  total  acidity  of  the  grapes  seems  to  be  less  influenced  by  varia- 
tions in  strength  of  alkali ;  three  of  the  varieties  show  an  increase  with 
increased  alkali.  This  increase  of  total  acidity  and  decrease  of  sugar 
content  in  strong  alkali  soils  is  doubtless  caused  by  the  diminished  vigor 
and  poor  growth  of  the  vines  in  such  soils. 

The  analysis  of  the  red  wine  varieties,  Trousseau  and  Meunier,  indi- 
cates a  slight  rise  of  tannin  with  increasing  strength  of  alkali  in  the 
soils;  this  increase  is,  however,  too  small  for  drawing  any  final  conclu- 
sions. 

The  above  results  seem  to  indicate  some  important  facts  worthy  of 
being  made  known.  First  of  all,  the  quality  of  wine  grapes  of  the 
Tulare  region  does  not  decrease  with  increasing  strength  of  alkali  in  the 
soil,  at  least  up  to  a  certain  limit  of  total  salts.  The  increase  of  total 
acidity  of  the  grapes  grown  in  stronger  alkali  is  of  special  value  in  the 
making  of  sound  wines  in  similar  localities,  while  the  decrease  of  sugar 
content  secures  at  the  same  time  a  wine  not  too  alcoholic.  The  practi- 
cal wine-making  experiments  with  Tulare  grapes,  undertaken  by  the 
Agricultural  Experiment  Station,  have  indicated  this  fact:  they  have 
shown  that  sound,  light  table-wines,  excellent  for  blending  purposes, 
or  as  light  neutral  wines  for  consumption,  could  be  made  of  grapes 
grown  on  such  alkali  soils. 

The  growing  of  raisin  grapes  in  strong  alkali  soils  can  not  be  recom- 
mended, as  the  tendency  of  the  sugar  content  to  decrease  with  increas- 
ing alkali  results  in  the  production  of  an  inferior  raisin. 


ORCHARD  CROPS. 

It  will  be  seen  that  the  list  in  the  table  below  comprises  the  chief 
orchard  crops  of  California ;  and  while  most  of  them  are  represented  in 
their  extremes  of  good  and  poor  growths,  there  are  a  few  which  could 
only  be  found  in  a  state  of  good  growth,  and  in  what  seemed  to  be 
strong  alkali. 


46 


UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION. 


Alkali  in  Soils  of  Orchards. 


Trees. 


A  Imonds — 
Tulare.    

Apples — 
Tulare— Red  Bietigheimer 

Ducht-ss 

Jonathan 

Apricots— 

Tulare 

Tulare 

Figs — 

Tulare— Osburn's  Prolific 
California  Black. 

Lemons — 

La  Mirada.         .. 

La  Mirada 

La  Mirada 

Olives — 

Tulare— Nigerina 

Regalis 

La  Mirada 

La  Mirada 

Kern  City 5  feet 

Oranges — 

Tulare 

Chino 

Corona 

Corona 

Corona 

Peaches— 

Tulare 

Tulare 

Hanford 

Pears  - 

Tulare   

Tulare 

Plums — 
Tulare 

Prunes  on  Myrobalan — 
Tulare....! 

Mulberry — 
Tulare 


Condition. 


Good 


Good  ... 
Affected 

Good  ... 
Good  ._. 

Good  „__ 
Stunted. 
Dead_.- 


Percentage  in  Soil. 


Good  .... 
Good  .... 
Good  .... 
Stun  ted.  . 
Dead  ... 

Fair 

Good   

Fair 

Poor    ... 
Poor 

Best 

Poor .... 
Poor    

Best 

Poor 

Verypoor 

Good  .... 

Good  .... 


.142 


.089 


Good 

Poor .117 

Poor .029 


054 
.214 

.153 

.068 

.028 
.032 
.039 

.192 
.126 
.025 
.271 
.245 

.062 
.155 
.018 
.028 
.029 

.060 

.084 
.088 

.111 
.239 

.140 

.058 
.021 


.009 

.004 
.008 
.005 

003 
.011 

.007 
.005 

.003 
.003 
.007 

.018 
.017 
.015 
.029 
.010 

.024 
.012 
.008 
.013 
010 

.004 
.007 
.002 

.011 
.013 

.011 

.009 

.001 


.015    .166 


.008 
.021 

.007 

.006 
.021 

.005 
.001 

.005 
.009 
.012 

.042 
.021 
.014 
.074 
.152 

.021 
.015 
.002 
.011 
.015 

.006 
.015 
.070 

.009 
.009 

.014 

.008 

.014 


.101 
.146 
.041 

.063 

.246 

.165 
.074 

.036 
.044 

.058 

.252 
.164 
.054 
.374 
.407 

.107 
.182 
.028 
.052 
.054 

.070 
.106 
.160 

.131 

.261 

.165 
.075 
.036 


Pounds  per  Acre:  4  ft.  depth. 


op 


o  5 

»  CD 


22,720 

1,440 

14,240 

18,760 
6,840 

640 
1,200 
1,080 

8,640 
34,240 

480 
1,760 

24,480 
10,880 

1,120 

760 

4,480 
5,120 
6,240 

480 

480 

1,120 

30,640 
20,160 
4,000 
43,360 
49,000 

2,880 
2,640 
2,400 
4,640 
2,000 

9,840 
18,600 
2,920 
4,520 
4,720 

3,840 
1,440 
1,280 
2,000 
1,680 

9,600 
13,400 
14,080 

680 

1,160 

320 

17,800 
38,280 

1,760 

2,080 

22,360 

1,760 

9,240 

1,360 

3,360 

160 

2,400 

1,240 
3,320 
1,720 

960 
3,260 

800 
160 

800 
1,440 
1,920 

6,640 

3,360 

2,240 

11,840 

30,400 

3,360 
1,800 
360 
1,800 
2,520 

1,000 

2,440 

11,200 

1,360 
1,360 

2,120 

1,200 

2,240 


>$ 


26,560 

16,120 

23,280 

9,640 

10,080 
39,2(10 

26,400 
11,800 

5,760 
7,040 

9,280 

40,160 
26,160 
8,640 
59,840 
81,400 

17,040 

21,840 

4,560 

8,320 

8,920 

11,280 
17,000 
25,600 

20,920 
41,720 

26,240 

11,800 

5,760 


Almonds. — The  almond  trees  of  the  Tulare  substation  are  isolated 
from  the  other  orchard  growths  and  were  all  in  a  healthy  condition  and 
loaded  with  fruit.  No  trees  have  been  found  whose  poor  condition  could 
be  attributed  to  alkali;  hence,  the  greatest  limit  of  tolerance  in  the 
almond'  has  as  yet  not  been  ascertained,  but  is  clearly  above  2,000 
pounds  of  carbonate  of  soda  and  3,000  pounds  of  common  salt  per  acre 
four  feet  deep. 

Apples.- -The  tree  is  quite  sensitive  to  alkali  salts,  and  their  effect 
on  the  foliage  of  the  tree  was  very  marked,  as  is  shown  in  the  accom- 
panying illustration  (Fig.  11).    The  newer  Limbs  of  the  tree  appear  as. 


3-o 

r>  dJ 


bco 
■43  t> 

03  o 

T3  fcC 


48  UNIVERSITY    OF   CALIFORNIA — EXPERIMENT    STATION. 

canes  with  a  tuft  of  leaves  at  the  upper  end,  instead  of  being  covered 
with  foliage  throughout,  as  is  also  shown  in  the  photograph.  Samples 
of  soil  were  taken  to  the  depth  of  four  feet  under  the  Duchess  of  Olden- 
burg, which  was  in  very  poor  condition,  with  no  fruit,  and  whose  top 
was  losing  Its  leaves ;  the  Jonathan,  also  very  poor,  and  the  Red 
Bietigheimer,  which  was  in  excellent  condition.  The  results  of  the 
examination  make  it  clear  that  while  the  apple  will  tolerate  the  presence 
of  14,000  pounds  of  sulfates,  650  of  carbonate  of  soda,  and  1,200  of 
common  salt,  it  is  injured  by  1,200  pounds  of  carbonate  and  3,000 
pounds  of  common  salt  per  acre  distributed  through  four  feet  depth. 
The  Jonathan  seems  to  be  more  sensitive  than  the  Duchess. 

Apricots.— The  trees  selected  as  representing  the  best  and  the  worst 
condition  respectively  were  grown  upon  their  own  stock.  The  differ- 
ences between  the  two  were  very  marked,  in  the  greater  height  and  full 
foliage,  large  leaves,  and  vigorous  growth  in  the  one,  and  the  thinner 
foliage,  smaller  and  blighted  leaves,  new  leaves  in  clusters  at  end  of 
limb,  and  evident  poor  health  in  the  other;  some  twigs  had  lost  their 
leaves  entirely.  The  accompanying  photograph  (Fig.  12)  shows  these 
effects.  The  results  of  the  examination  of  the  respective  soils  show  that 
while  the  total  alkali  and  that  of  each  salt  are  greater  in  the  soil  of 
the  poor  tree,  and  that  to  either  of  these  might  be  attributed  the  trouble, 
it  is  more  than  likely  that  either  the  sulfate  or  the  common  salt  is  the 
true  cause ;  for  their  amounts  are  excessive,  while  that  of  the  carbonate 
is  lower  than  what  is  tolerated  by  most  cultures. 

Figs.— The  tree  easily  tolerated  as  much  as  25,000  pounds  of  glauber 
salt  and  1,100  pounds  of  carbonate  of  soda  per  acre  in  four  feet. 

Lemons. — The  lemon  seems  to  be  the  least  tolerant  of  all  of  the  fruit 
trees,  for  it  was  apparently  stunted  by  only  1,440  pounds  of  common 
salt  per  acre  distributed  through  four  feet  depth,  and  was  killed  by 
1,900  pounds  combined  with  1,900  pounds  of  carbonate  of  soda.  Its 
endurance  of  carbonate  of  soda  has  not  been  ascertained. 

Oranges.— From  the  culture  experiments  at  Tulare  substation  it 
would  seem  that  oranges  do  fairly  well  in  the  presence  of  3,840  pounds 
of  carbonate  and  3,360  pounds  of  common  salt  per  acre  in  four  feet 
depth,  or  a  total  of  17,040  pounds  of  alkali.  The  examinations  at 
Corona  seem  to  contradict  this,  for  there  the  trees  suffered  in  1,680 
pounds  of  carbonate  and  2,500  pounds  of  common  salt.  The  expla- 
nation is  that  the  conditions  surrounding  the  trees  were  different,  for  at 
Tulare  a  detailed  examination  shows  that  the  salts  were  distributed 
through  the  four  feet  of  soil  quite  evenly,  while  at  Corona  the  common 
salt  was  all  contained  in  the  first  two  feet.     Then,  too,  at  Tulare  the 


4— bul.  128-133 


50  UNIVERSITY    OF   CALIFORNIA — EXPERIMENT   STATION. 

\ 

roots  of  the  tree  were  by  proper  culture  encouraged  to  send  their  feed- 
ing roots  to  a  depth  of  seven  or  eight  feet  below  the  surface,  while  at 
Corona  the  system  of  shallow  furrow-irrigation  so  much  practiced  in 
southern  California  had  compelled  the  roots  to  remain  within  a  short 
distance  of  the  surface  of  the  soil  to  secure  necessary  moisture,  and 
hence  the  salt  concentrated  near  the  surface  could  act  with  greater 
energy. 

Thus  is  emphasized  the  importance  of  the  oft-repeated  injunction  to 
so  use  irrigation  water  and  cultivation  as  to  permit  the  roots  of  trees  to 
follow  their  natural  tendency  of  penetrating  deeply  into  the  soil.  Had 
the  salts  in  the  Corona  soils  been  distributed  through  a  greater  depth 
the  trees  would  doubtless  have  withstood  the  effects  of  the  alkali  much 
longer.  In  fact,  since  the  publication  of  the  Station  Report  of  1898,  the 
orchardists  of  Corona  have  very  greatly  improved  their  groves  by  this 
treatment  and  the  use  of  pure  water;  and  the  particular  orchard  there 
shown  as  typical  of  the  effects  of  alkali  has  now  recovered  its  vigor  and 
foliage. 

Olives. — The  olive  trees  of  the  Tulare  substation  were  all  in  good  con- 
dition when  visited,  though  some  stood  in  soils  quite  highly  charged 
with  alkali  salts.  Of  those  represented  in  the  table  the  Precox  was  in 
a  sandy  soil,  while  the  Regalis  and  Nigerina  were  in  loams.  Samples 
of  soil  were  also  sent  to  this  office  from  an  olive  orchard  near  La 
Mirada,  Los  Angeles  County,  by  the  manager.  One  lot  of  samples  was 
from  the  high  part  of  the  orchard,  where  the  trees  were  large  and 
healthy;  the  other  lot  was  from  lower  land,  where  the  trees  were  six 
years  old,  but  stunted  (four  feet  high)  ;  the  same  treatment  had  been 
given  the  trees  in  both  cases.  Another  series  of  samples  was  sent  by 
the  manager  of  an  olive  orchard  near  Kern  City,  Kern  County,  in 
which  the  trees  were  suffering.  The  results  of  examination  are  shown 
in  the  table. 

The  olive  tree  is  clearly  immune  to  as  much  as  3,000  pounds  of 
carbonate  of  soda  (black  alkali)  and  30,000  pounds  of  glauber  salt  per 
acre  in  four  feet,  and  the  limit  of  tolerance  will  probably  be  found  to 
be  much  above  those  figures. 

The  tolerance  for  common  salt  is  above  6,000  pounds  per  acre  in  four 
feet,  for  the  Nigerina  did  well  in  about  that  amount.  At  La  Mirada  the 
trees  were  stunted  in  presence  of  11,800  pounds,  and  killed  in  an  orchard 
near  Kern  City  where  there  was  19,500  pounds  in  four  feet  depth  and 
30,400  pounds  in  five  feet.  At  Kern  City,  however,  the  greater  part  of 
the  alkali  was  contained  in  the  soil  below  a  depth  of  two  feet,  and  had 
the  examination  gone  deeper  than  five  feet  there  would  doubtless  have 
been  found  in  all  about  50,000  pounds  of  common  salt  in  a  total  of  over 
100,000  of  alkali  salts. 


TOLERANCE  OF  ALKALI  BY  ORCHARD   CROPS.  51 

The  following  method  of  planting  the  trees  adopted  by  the  owner  of 
the  latter  orchard  has  enabled  them  to  secure  a  good  growth  before  the 
roots  felt  the  effects  of  the  alkali,  and  illustrates  the  importance  with 
some  cultures  of  forcing  the  alkali  down  to  quite  a  depth  by  the  use 
of  plenty  of  water  and  allowing  the  plant  to  secure  a  foothold : 

The  holes  for  the  trees  are  made  three  feet  deep  and  as  wide,  several 
months  before  planting;  near  planting  time  they  are  partially  rilled  with 
good  soil  and  filled  with  water.  When  the  water  has  seeped  down,  the 
holes  are  filled  with  top  soil  and  the  trees  planted.  The  alkali  is  thus 
washed  beyond  the  depth  of  the  roots.  There  is  hardly  a  doubt  but 
that  if  there  had  not  been  such  an  enormous  amount  of  alkali  in  the 
lower  four  or  five  feet  the  trees  would  have  successfully  resisted  its  effect 
on  the  roots. 

Peaches.— The  trees  at  the  Tulare  substation  were  in  part  in  fairly 
good  and  in  part  in  poor  condition,  and  samples  of  soils  were  taken  from 
the  best  representatives  of  each.  Both  were  on  peach  stock,  and  the 
difference  in  appearance  was  in  smaller  leaves  and  general  unhealthy 
growth,  due  to  either  the  common  salt  or  carbonate  as  shown  in  the  table. 

From  the  region  of  Hanford,  Kings  County,  peach  trees  were  reported 
as  being  in  bad  condition.  The  examination  of  this  soil  shows  the 
presence  of  an  enormous  amount  (11,200  pounds)  of  common  salt  in 
the  four  feet,  to  which  doubtless  the  dying  of  the  trees  must  be 
attributed. 

The  results  obtained  at  Tulare  make  it  probable  that  the  limits  of 
alkali  tolerated  by  peach  trees  may  be  placed  at  10,000  pounds  of  sul- 
fates, 750  of  carbonate,  and  1,200  of  common  salt  per  acre  in  four  feet 
depth. 

Pears.— The  effect  of  alkali  upon  the  pear  was  noticed  only  in  the 
orchard  of  the  Tulare  substation,  where  quite  a  large  block  of  land  is 
given  to  its  culture.  Through  the  central  part  of  this  lies  a  belt  of  alkali 
which  has  seriously  injured  some  of  the  trees,  the  leaves  turning  yellow 
or  blackening  at  the  tips,  and  others  being  killed.  On  either  side  of  this 
belt  the  trees  are  in  good  condition  and  bear  well.  Samples  of  soil  were 
taken  under  LeConte  and  Keiffer  trees  which  were  yielding  to  alkali, 
showing  the  yellow  leaves  with  blackened  tips ;  they  had  no  fruit. 

The  samples  from  the  "best  trees"  are  from  the  northern  part  of  the 
pear  block.  The  trees  are  Kennedy  varieties  and  were  planted  long 
before  the  alkali  had  encroached  on  them ;  so  that  their  roots  have 
escaped  attack,  although  the  amount  of  alkali  is  greater  than  under  the 
other  trees. 

The  results  would  seem  to  show  that  while  the  pear  can  tolerate  as 
much  as  1,400  pounds  of  common  salt  and  1,800  pounds  of  carbonate 
per  acre  in  four  feet,  it  is  seriously  affected  by  38,000  pounds  of  the 


52 


UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION. 


sulfate,  for  it  is  hardly  possible  that  an  addition  of  320  pounds  of  car- 
bonate in  the  four  feet  per  acre  would  produce  the  damage. 

In  another  locality  the  trees  were  killed  in  land  whose  surface  soil 
contained  4,600  pounds  of  carbonate  and  18,000  pounds  of  common  salt 
in  a  total  of  62,000  pounds. 


.  « 
*  p-i 


o3   fa 

O 


Plums.— The  Robe  de  Sergent  plum  at  the  Tulare  substation  is  on  its 
own  stock  and  suffering  very  severely  from  alkali,  as  shown  in  the 
photograph  on  Fig.  13.  The  tree  was  dwarfed,  and  the  limbs  were 
losing  their  leaves.     The  amount  of  alkali  in  this  case  was  not  large, 


TOLERANCE  OF  ALKALI  BY  TREES.  53 

only  26,240  pounds,  and  amounts  of  the  carbonate  and  common  salt 
were  also  comparatively  small.  This  plum,  therefore,  is  one  of  the 
most  sensitive  of  trees  to  the  effects  of  alkali  salts. 

Prunes.— Prune  trees,  if  grown  on  Myrobalan  stock,  should  be  highly 
tolerant  of  alkali  salts,  for  that  stock  is  a  native  of  Asia  Minor,  where 
alkali  abounds.  We  have  thus  far  been  unable  to  secure  samples  of 
soil  where  the  trees  showed  the  effect  of  alkali.  At  the  Tulare  sub- 
station the  amount  in  their  soils  was  only  about  12,000  pounds  per  acre 
in  four  feet,  and  of  this  only  1,360  was  of  carbonate  and  1,200  of 
common  salt.  It  is  said  that  at  Hanford,  Kings  County,  the  prune 
flourishes  in  alkali  soils  where  the  peach  is  severely  affected;  we  may 
therefore  place  the  power  of  tolerance  at  quite  high  figures  for  common 
salt  at  least.  If  it  be  true  that  this  fruit  tree  can  withstand  a  very 
large  amount  of  common  salt  it  will  prove  of  great  value  in  alkali 
regions,  for  the  carbonate  of  soda  part  of  alkali  can  easily  be  neutralized 
by  gypsum. 

Walnuts.— Samples  of  soil  were  sent  from  an  orchard  near  Anaheim, 
Orange  County,  in  which  "walnut  trees  have  been  planted,  but  they 
soon  died  and  the  roots  rotted  very  quickly,  while  outside  of  this  spot 
they  do  exceptionally  well."  The  examination  of  the  samples  showed 
the  presence  of  18,000  pounds  of  common  salt  and  about  the  same 
amount  of  sulfates  per  acre  in  four  feet  depth. 

TIMBER   AND    SHADE    TREES. 

Of  trees  suitable  for  alkali  lands,  two  native  ones  call  for  mention. 
One  is  the  California  white  or  valley  oak  (Quercus  lobata) ,  which 
forms  a  dense  forest  of  large  trees  on  the  delta  lands  of  the  Kaweah 
River  in  California,  and  is  found  scatteringly  all  over  the  San  Joaquin 
Valley.  Unfortunately,  this  tree  does  not  supply  timber  valuable  for 
aught  but  firewood  or  fence  posts,  being  quite  brittle.  The  native 
cottonwoods,  while  somewhat  retarded  and  dwarfed  in  their  growth  in 
strong  alkali,  are  quite  tolerant  of  the  white  salts,  especially  of  glauber 
salt. 

Of  other  trees,  the  oriental  plane,  or  sycamore,  and  the  black  locust, 
have  proved  the  most  resistant  in  the  alkali  lands  of  the  San  Joaquin 
Valley ;  and  the  former  being  a  very  desirable  shade  tree,  it  should  be 
widely  used  throughout  the  regions  where  alkali  prevails  more  or  less. 
The  ailantus  is  about  equally  resistant,  and  but  for  the  evil  odor  of  its 
flowers,  deserves  strong  commendation.  Of  the  eucalypts,  the  narrow- 
leaved  Eucalyptus  amygdalina  (one  of  the  "red  gums")  seems  to  be 
least  sensitive,  and  in  some  cases  has  grown  as  rapidly  as  anywhere. 


54  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION. 

The  E.  rostrata,  as  well  as  the  pink-flowered  variety  of  E.  sideroxylon, 
are  now  doing  about  as  well  as  the  amygdalina  at  Tulare,  where  at  first 
they  seemed  to  suffer.  The  common  blue  gum,  E.  globulus,  is  much 
more  sensitive. 

Of  the  acacias,  the  tall-growing  A.  melanoxylon  ("black  acacia") 
resists  pretty  strong  alkali,  even  on  stiff  soil ;  as  can  be  seen  at  Tulare 
and  Bakersfield,  where  there  are  trees  nearly  two  feet  in  diameter.  The 
beautiful  A.  lophantha  (Albizzia)  has  in  plantings  made  along  the  San 
Joaquin  Valley  Railroad  shown  considerable  resistance,  likewise;  but 
it  is  quite  sensitive  to  frost. 

One  of  the  "Australian  pines,  Casuarina  equisetifolia,"  was  trans- 
planted experimentally  on  station  grounds  of  the  Valley  Railroad  from 
the  Chico  forestry  substation,  and  a  number  are  growing  very  well  in 
alkali  lands.  This  tree  is  credited  by  Maiden  with  being  tolerant  of 
"saline  soil."  Doubtless  many  others  of  the  Casuarina  tribe  will  be 
found  similarly  resistant. 

Of  Eastern  trees,  the  elms  have  done  fairly  well,  but  the  tulip  tree, 
the  linden,  the  English  oak,  and  most  other  trees  of  the  Atlantic  States, 
become  stunted.  Among  those  doing  fairly  well  is  the  honey  locust; 
but  its  thorns  and  imperfect  shade  render  it  not  very  desirable. 

The  California  maple  (Acer  macrophyllum)  and  box  elder  (Negundo 
calif  or  nica)  have  done  fairly  well  in  the  lighter  alkali  lands  at  Tulare. 

A  most  remarkably  alkali-resistant  shrub  or  small  tree  is  the  pretty 
Koelreuteria  paniculata,  which  at  Tulare  is  growing  in  some  of  the 
strongest  alkali  soil  of  the  tract  (.062  per  cent  or  about  10,000  pounds 
in  four  feet  per  acre).  Unfortunately  it  is  available  mainly  for  orna- 
mental purposes ;  its  wood,  while  small,  is  very  hard  and  makes  excellent 
fuel. 

A  number  of  Washingtonia  palms  are  growing  along  the  border  of  the 
Tulare  station  tract  and  county  road,  in  soils  containing  about  .097 
per  cent  or  15,000  pounds  of  alkali  salts  per  acre.  The  palms  look  well 
and  none  of  them  seem  to  have  been  affected  by  alkali. 

A  large  date  palm  is  growing  in  a  sandy  alkali  soil  at  the  Tulare 
substation  and  is  not  at  all  affected  by  the  two  hundredths  of  one  per 
cent  (2,800  pounds  per  acre)  of  carbonate  of  soda  present.  It  will 
clearly  tolerate  a  larger  amount.  Only  a  trace  of  common  salt  was 
found  in  the  soil. 

The  carbonate  of  soda  around  the  roots  of  a  large  Oriental  sycamore 
tree  is  comparatively  small  (.020  per  cent  or  3,200  pounds  per  acre), 
but  common  salt  is  present  to  the  extent  of  more  than  one  tenth  of  one 
per  cent,  which  gives  the  enormous  amount  of  20,000  pounds  per  acre 
in  four  feet  depth.  It  is  clear,  then,  that  in  almost  any  alkali  land 
reclaimed  from  carbonate  of  soda  this  tree  will  make  good  growth. 


TOLERANCE   OF   ALKALI;    GENERAL   SUMMARY. 


55 


GENERAL   SUMMARY   OF  RESULTS   THUS   FAR   OBTAINED. 

The  following  tables  present  in  brief  form,  for  comparison,  the  nearest 
approach  to  maximum  tolerance  of  each  of  the  salts  of  alkali  thus  far 
obtained  for  fruits  and  other  cultures;  giving,  of  course,  the  amounts 
in  which  each  culture  was  growing  and  in  good  condition  entirely 
unaffected  by  alkali.  The  cultures  are  arranged  in  the  order  of  highest 
tolerance. 

These  results  are  of  course  only  tentative,  for  in  a  great  majority  of 
cases  future  examinations  will  probably  greatly  raise  the  figures  given 
in  the  tables. 

Highest  Amount  of  Alkali  in  Which  Fruit  Trees  Were  Found  Unaffected. 

Arranged  from  highest  to  lowest.    Pounds  per  acre  in  four  feet  depth. 


Sulfates 

Carbonate 

Chlorid 

(Glauber  Salt). 

(Sal  Soda) 

(Common  Salt). 

■Grapes 

40,800 

Grapes 

7,550 

Grapes 

9,640 

Grapes 

45,760 

Olives 

30,640 

Oranges 

3,840 

Olives 

6,640 

Olives 

40,160 

Figs 

24,480 

Olives 

2,880 

Oranges 

3,360 

Almonds 

26,560 

Almonds 

22,720 

Pears 

1,760 

Almonds 

2,400 

Figs 

26,400 

Oranges 

18,600 

Almonds 

1,440 

Mulberry 

2,240 

Oranges 

21,840 

Pears 

17,800 

Prunes 

1,360 

Pears 

1,360 

Pears 

20,920 

Apples 

Peaches  

14,240 

Figs. 

1,120 

680 

Apples 

Prunes 

1,240 

Apples 

Prunes 

16,120 
11,800 

9,600 

Peaches 

1,200 

Prunes 

9,240 

Apples 

640 

Peaches 

1.000 

Peaches  

11,280 

Apricots 

8,i»40 

Apricots 

480 

Apricots 

9(50 

Apricots 

10,080 

Lemons 

4,480 

Lemons 

480 

Lemons 

800 

Lemons 

5,760 

Mulberry 

3,360 

Mulberry 

160 

Figs 

800 

Mulberry 

5,760 

Other  T 

pees. 

Kolreuteria  _. 

51,040 

Kolreuteria  . 

9,920 

Or.  Sycamore 

20,320 

Kolreuteria  .. 

73,600 

Eucal.am 

34,720 

Or.  Sycamore 

3,200 

Kolreuteria  . 

12,640 

Or.  Sycamore 

42,760 

Or.  Sycamore. 

19,240 

Date  Palms.. 

2,800 

Eucal.  am.  __ 

2,960 

Eucal.am 

40,400 

Wash.  Palms. 

13,040 

Eucal.  am.  __ 

2,720 

Camph. Tree- 

1,420 

Wash.  Palms. 

15,280 

Date  Palms ... 

5,500 

Wash.  Palms 

1,200 

Wash.  Palms 

1,040 

Date  Palms... 

8,320 

Camph.  Tree . 

5,280 

Camph.  Tree. 

3?0 

Camph.  Tree  . 

7,020 

Small  C 

ultures. 

Saltbush 

125,640 

Saltbush 

18,560 

Modiola 

40,860 

Saltbush 

156,720 

Alfalfa,  old... 

102,480 

Barley 

12,170 

Saltbush 

12,520 

Alfalfa,  old... 

110,320 

Alfalfa,  young 

11,120 

Bur  Clover ._ 

11,300 

Sugar  Beet*. 

11,900 

Alfalfa,  young 

'  13,120 

Hairy  Vetch.. 

63,720 

Sorghum 

9,840 

Sorghum 

9,680 

Sorghum 

81,360 

Sorghum 

61,840 

Radish 

8,720 

Celery 

9,600 

Hairy  Vetch.. 

69,360 

Sunflower  ... 

52,640 

Modiola 

4,760 

Potatoes 

5,810 

Radish.   

62,840 

Radish 

51,880 

Sugar  Beet ._ 

4,000 

Onions 

5,810 

Sunflower 

59,840 

Sugar  Beet   .. 

48,560 

GlutenWheat 

3,000 

Alfalfa,  old.. 

5,760 

Sugar  Beet*.. 

54,480 

Artichoke  ... 

38.720 

Artichoke    ._ 

2,760 

Alfalfa, yo'ng 

760 

Modiola 

52,420 

Potatoes 

32,530 

Lupin    

2,720 

Sunflower... 

5,440 

Artichoke 

42,960 

Onions 

32,530 

Hairy  Vetch. 

2,480 

Barley 

5,100 

Potatoes 

38,340 

Oarrot 

24, 8H) 

Alfalfa 

2,360 

Hairy  Vetch 

3,160 

Onions 

38,340 

Gluten  Wheat  20,960 

Grasses 

2,300 

Lupin. 

3,040 

Carrot 

28,480 

Wheat. 

15,120 

Kaffir  Corn.. 

1,800 

Carrot  + 

2,600 

Barley 

25,520 

Barley 

12,020 

Sweet  Corn.. 

1,800 

Radish 

2,240 

Gluten  Wheat 

.  24,320 

Goat's  Rue    .. 

10,h80 

Sunflower ... 

1,760 

Rye 

1,720 

Wheat 

17,280 

Rye 

9,800 

Wheat 

1,480 

Sweet  Peas.. 

1,500 

Bur  Clover... 

17,C00 

Canaigre 

9,100 

Carrot  

1,240 

Artichoke ... 

1,480 

Celery 

13,680 

Ray  Grass 

6,920 

Rye .... 

960 

GlutenWheat 

1,480 

Rye 

12,480 

Modi'>la 

6,800 

Goat's  Rue.. 

760 

Wheat 

1,160 

Goat's  Rue... 

11,800 

Bur  Clover ... 

5,700 

WhiteMelilot 

480 

Grasses 

1,000 

Lupin 

11,200 

Lupin 

5.440 

Canaigre 

120 

WhiteMelilot 

440 

Cafiaiecre 

9,360 

White  Melilot    4,920 

Goat's  Rue .. 

160 

Ray  Grass 

6,920 

Celery 

4,080 

White  Melilot    5,840 

*In3feet.    f  In  1  foot, 


56  UNIVERSITY    OF   CALIFORNIA — EXPERIMENT   STATION. 


IRRIGATION  WITH  SALINE  WATERS. 

It  would  hardly  seem  necessary  to  emphasize  specially  the  danger 
incurred  in  irrigation  with  waters  containing  unusual  amounts  of  solu- 
ble salts ;  since  ordinary  common  sense  clearly  indicates  the  impropriety 
of  increasing  the  saline  contents  of  soils  already  charged  with  them,  by 
the  evaporation,  year  after  year,  of  large  masses  of  saline  water.  Yet 
experience  has  shown  that  the  eagerness  to  utilize  for  irrigation  what- 
ever water  happens  to  be  convenient  to  good  lands,  often  overcomes 
both  that  sense,  and  the  warning  given  by  the  published  analyses  of  such 
waters.  Without  specifying  localities,  it  may  be  said  that  great  injury 
has  already  been  done  in  California  by  the  disregard  of  obviously 
needful  caution  in  this  respect.  The  very  slight  taste  possessed  by 
glauber  salt  and  salsoda  does  not  adequately  indicate  their  presence 
even  when  in  injurious  amounts;  so  that  frequently  a  chemical  test  of 
the  waters  is  the  only  definite  guide.  A  few  general  rules,  however, 
will  help  to  enable  the  irrigator  to  determine  whether  or  not  such 
examination  is  called  for. 

It  may  be  taken  for  granted  that  the  waters  of  all  lakes  having  no 
regular  outflow  are  unfit  for  regular  irrigation  use;  since  they  must 
needs  contain  all  the  accumulations  of  salts  from  the  secular  evaporation 
of  the  waters  that  flow  into  them. 

The  plates  annexed  exhibit  the  cultural  results  of  several  years r 
irrigation  with  the  waters  of  Lake  Elsinore,  Riverside  County,  as  com- 
pared with  the  growth  of  orange  trees  on  the  same  land,  but  irrigated 
with  artesian  water.  Lake  Elsinore  is  fed  by  the  San  Jacinto  River, 
and  in  wet  years  sometimes  overflows  for  a  few  weeks  into  Temescal 
Creek.  Thus  its  saline  content  varies  somewhat,  from  about  80  to  over 
100  grains  per  gallon,  of  salts  containing  three-fifths  of  common  salt 
and  one-fifth  each  of  glauber  salt  and  carbonate  of  soda.  The  latter, 
as  already  stated,  tends  to  form  a  hardpan  in  the  subsoil,  and  such 
hardpan  was  actually  formed  where  the  water  was  used ;  and  afterwards 
prevented  its  proper  penetration,  so  that  the  trees  suffered  from  dry- 
ness of  their  lower  roots,  while  damaged  by  the  alkali  salts  near  the- 
surface.  As  mentioned  before,  experience  elsewhere  has  shown  that 
citrus  trees  are  especially  sensitive  to  common  salt. 

The  investigations  made  by  the  Station  have,  moreover,  shown  that 
aside  from  the  frequently  saline  character  of  the  well  and  even  the 
artesian  waters  of  the  petroleum-bearing  region  of  the  State  in  the  coast 
ranges,  the  streams  of  that  region,  especially  the  smaller  ones,  are  some- 
times too  strongly  charged  with  "alkali"  (in  this  case  largely  the 
sulfates  of  soda  and  magnesia)  to  be  suitable  for  either  irrigation  or 
domestic  use.    Toward  the  end  of  the  dry  season,  even  the  larger  streams 


IRRIGATION  WITH  SALINE  WATERS.  57 

of  the  southern  coast  ranges,  with  their  diminished  flow,  sometimes 
show  an  excess  of  salts.  This  seems  also  to  be  true  of  the  San  Jacinto 
River,  which  feeds  Elsinore  Lake. 

The  waters  flowing  from  the  Sierra  Madre,  south  of  the  Tehachapi 
range,  are  throughout  of  excellent  quality  for  irrigation  purposes;  as 
are  all  those  flowing  from  the  Sierra  Nevada.  The  same  is  true  of  the 
artesian  waters  of  the  valley  of  southern  California,  from  Los  Angeles 
east  to  Redlands,  and  of  all  the  deeper  borings  of  the  Antelope  Valley. 

In  the  Great  Valley,  the  artesian  waters  vary  greatly  in  quality.  Those 
of  Kern  and  Tulare  counties  are  mostly  good,  sometimes  exceptionally 
so,  as  in  the  case  of  the  water-supply  of  Tulare  City.  It  is  only  in  the 
shallower  borings,  near  the  borders  of  Tulare  Lake,  that  some  waters 
strongly  charged  with  carbonate  of  soda  or  other  salts  have  been  found. 
From  Fresno  and  Merced  we  have  few  data  as  yet;  but  it  seems  that 
north  of  a  line  drawn  from  northeastern  Stanislaus  via  Tracy  to  Point 
of  Timber,  saline  waters,  sometimes  accompanied  by  some  gas,  occur  at 
certain  levels.  But  the  deep  wells  bored  at  Stockton  and  Sacramento, 
and  northward,  have  good  potable  water. 

Limits  of  Saline  Co ntents.— Unfortunately  it  is  not  easy  to  give  abso- 
lute rules  in  regard  to  the  exact  figures  that  constitute  an  excess  of  salts 
for  irrigation  purposes,  since  not  only  the  composition  of  the  salts, 
but  also  the  nature  of  the  land  to  be  irrigated,  and  the  frequency  and 
amount  of  irrigation  water  required,  must  be  taken  into  consideration. 

Broadly  speaking,  the  extreme  limits  of  mineral  content  usually 
assigned  for  potable  waters,  viz,  40  grains  per  gallon,  also  applies  to 
irrigation  waters.  Yet  it  sometimes  happens  that  all  or  most  of  the 
solid  content  is  gypsum  and  epsom  salt;  when  only  a  large  excess  of 
the  latter  would  constitute  a  bar  to  irrigation  use.  When,  on  the  con- 
trary, a  large  proportion  of  the  solids  consists  of  carbonate  of  soda  or 
of  common  salt,  even  a  smaller  proportion  of  salts  than  40  grains 
might  preclude  its  regular  use,  depending  upon  the  nature  of  the  soil 
to  be  irrigated.  For  in  a  clay  loam,  or  a  heavy  adobe,  not  only  do  the 
salts  accumulate  nearer  to  the  surface,  but  the  subdrainage  being  slow 
and  imperfect  (unless  underdrained),  it  becomes  difficult  or  impossible 
to  wash  out  the  saline  accumulations  from  time  to  time,  as  is  feasible 
in  sandy  lands.  In  these,  moreover,  as  already  stated,  the  alkali  never 
becomes  as  concentrated  near  the  surface  as  in  heavier  soils.  Again, 
where  hardpan  exists  in  sandy  land,  saline  irrigation-water  soon  sat- 
urates the  soil  mass  above  it  with  salts. 

It  has  been  observed  by  Means  that  in  the  Algerian  Sahara  region, 
where  the  date  palm  is  extensively  grown  in  very  sandy  land,  the  trees 


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60  UNIVERSITY    OF   CALIFORNIA — EXPERIMENT   STATION. 

are  irrigated  regularly  with  water  that  contains  as  much  as  213  grains 
of  alkali  salts  per  gallon.  The  great  depths  and  perviousness  of  these 
lands,  together  with  the  fact  that  alkaline  salts  do  not  accumulate  near 
the  surface  in  very  sandy  materials,  explain  the  tolerance,  by  the 
palms,  of  these  waters,  which  are  moreover  used  in  great  abundance. 

During  the  dry  seasons  just  past  saline  waters  have  frequently 
been  used,  exceptionally,  in  order  to  save  trees  threatened  with  death 
from  drought.  The  Station  has  even  advised  that  this  should  be  done, 
with  the  proviso  that  the  salts  so  introduced  must  he  ivashed  into  the 
subdrainage  by  heavy  irrigation,  whenever  practicable,  even  if  the  same 
saline  water  should  have  to  be  used  for  the  purpose.  For  few  such 
waters  are  sufficiently  strong  to  injure  vegetation  until  concentrated  by 
evaporation;  as  can  be  seen  from  the  vegetation  growing  close  to  the 
margins  of  alkaline  lakes,  with  its  roots  immersed  in  the  water. 

The  irrigator  can  determine  for  himself  whether  or  not  his  water  is 
of  doubtful  character,  by  evaporating  a  tablespoonful,  or  more,  in  a 
clean  silver  spoon  (avoiding  boiling).  If  the  dry  residue  should  form 
simply  a  thin,  powdery-looking  film  on  the  polished  metal,  he  may  be 
assured  that  the  water  is  all  right.  If,  on  the  other  hand,  an  obvious 
saline  crust  should  remain,  which  will  redissolve  in  water,  he  should 
either  have  an, analysis  made,  or  use  the  water  in  such  a  manner  as  to 
remove  the  accumulated  salts  from  time  to  time  by  washing  them  into 
the  subdrainage,  if  the  nature  of  the  soil  permits.  A  very  abundant  use 
of  such  waters  is  then  preferable  to  a  sparing  one;  but  the  user  should 
assure  himself  that  it  really  penetrates,  for  otherwise,  especially  in  case 
much  carbonate  of  soda  is  present,  a  dense  hardpan  may  be  formed  that 
will  allow  the  trees  to  perish  from  drought  despite  all  the  water  running 
in  the  irrigation  furrows,  A  pointed  steel  probe,  three-sixteenths  of  an 
inch  square,  provided  with  a  cross-handle,  like  a  hand  auger,  ought 
to  be  among  the  tools  of  every  farmer  for  such  tests  of  his  subsoil. 
No  farmer  in  the  arid  region  can  afford  to  be  ignorant  of  the  nature 
of  the  substrata  within  which  the  bulk  of  the  roots  of  his  crops  must 
vegetate. 


NATURAL  VEGETATION  OF  ALKALI  LAND.  61 


RECLAIMABLE  AND  IRRECLAIMABLE  ALKALI  LANDS  AS   DISTINGUISHED 
BY  THEIR  NATURAL  VEGETATION. 

While,  as  shown  above,  the  adaptation  or  non-adaptation  of  par- 
ticular alkali  lands  to  certain  cultures  may  be  determined  by  sampling 
the  soil  and  subjecting  the  leachings  to  chemical  analysis,  it  is  obvi- 
ously desirable  that  some  other  means,  if  possible  available  to  the 
farmer  himself,  should  be  found  to  determine  the  reclaimability  and 
adaptation  of  such  lands  for  general  or  special  cultures. 

The  natural  plant  growth  seems  to  afford  such  means,  both  as 
regards  the  quality  and  quantity  of  the  saline  ingredients.  The  most 
superficial  observation  shows  that  certain  plants  indicate  extremely 
strong  alkali  lands  where  they  occupy  the  ground  alone;  others  indi- 
cate preeminently  the  presence  of  common  salt ;  the  presence  or  absence 
of  stili  others  form  definite  or  probable  indications  of  reclaimability  or 
non-re  claimability.  Many  such  characteristic  plants  are  well  known 
to  and  readily  recognized  by  the  farmers  of  the  alkali  districts. 
1 '  Alkali  weeds ' '  are  commonly  talked  about  almost  everywhere ;  but  the 
meaning  of  this  term— i.  e.,  the  kind  of  plant  designated  thereby— 
varies  materially  from  place  to  place,  according  to  climate  as  well  as  to 
the  quality  of  the  soil.  Yet  if  these  characteristic  plants  could  be 
definitely  observed,  described,  and  named,  while  also  ascertaining  the 
amount  and  kind  of  alkali  they  indicate  as  existing  in  the  land,  lists 
could  be  formed  for  the  several  districts,  which  would  indicate,  in  a 
manner  intelligible  to  the  farmer  himself,  the  kind  and  degree  of 
impregnation  with  which  he  would  have  to  deal  in  the  reclamation 
work,  thus  enabling  him  to  go  to  work  on  the  basis  of  his  own  judg- 
ment, without  previous  reference  to  this  Station. 

The  carrying-out  of  such  a  plan  involves,  obviously,  a  very  large 
amount  of  botanical  as  well  as  chemical  work,  which  can  not  be  accom- 
plished within  a  few  seasons;  and,  in  view  of  the  wide  differences  in 
the  vegetation  of  the  several  alkali  regions  of  the  State,  the  same  work 
will  have  to  be  repeated  to  a  certain  extent  in  each  of  these  regions. 
The  object  to  be  achieved  is,  however,  of  such  high  practical  impor- 
tance—an importance  not  remotely  appreciated  as  yet  by  those  not 
familiar  with  the  enormous  extent  of  otherwise  desirable  lands  in  this 
State  that  are  more  or  less  tainted  with  alkali— as  to  deserve  the 
expenditure  upon  it  of  a  large  amount  of  work  as  promptly  as  possible. 

The  extreme  limitation  of  funds  under  which  the  Agricultural  Col- 
lege and  Experiment  Station  have  been  suffering  for  years,  has  thus 
far  restricted  the  scope  of  these  researches  very  closely,  both  geographi- 
cally and  otherwise.  It  is  hoped  that  in  the  future,  a  close  comparison 
of  the  native  vegetation  with  the  chemical  determination  of  the  quantity 


62  UNIVERSITY    OF    CALIFORNIA  —  EXPERIMENT    STATION. 

and  kind  of  alkali  corresponding  to  certain  plants,  or  groups  of  plants, 
naturally  occurring  on  the  land,  may  enable  us  to  come  to  a  sufficiently 
close  estimate  of  the  nature  and  capabilities  of  the  latter  from  the 
native  vegetation  alone,  or  with  the  aid  of  test  plants  purposely  grown. 
But  before  entering  upon  this  complex  problem,  it  has  been  thought 
best  to  determine,  first  of  all,  what  lands  may  for  present  economic 
conditions  be  considered  irreclaimable,  because  their  improvement  would 
involve  an  expense  out  of  proportion  with  present  land  values.  So  far 
as  large  areas  are  concerned,  this  may  probably  be  considered  to  be  the 
ease  when  tile  underdrainage  is  required  in  order  to  wash  out  the  salts ; 
while  of  course  smaller  tracts,  which  interrupt  the  cultivation  of  fields, 
may  frequently  justify  the  laying  of  a  few  drain  lines  required  to  render 
them  cultivable  with  the  rest  of  the  land. 

As  stated  in  the  report  of  this  Station  for  1895-7,  the  field  work  of 
this  investigation,  both  botanical  and  in  the  collection  of  the  corre- 
sponding soil  samples,  has  been  done  by  Mr.  Joseph  Burtt  Davy, 
Assistant  Botanist  to  the  Station,  who  also  supplies  the  notes  accom- 
panying the  same ;  while  the  laboratory  work  for  the  determination  of 
the  amounts  and  kinds  of  salts  present  in  the  several  cases  has  been 
carried  out  by  Prof.  R.  H.  Loughridge. 

The  plants  hereinafter  mentioned,  and  figured  for  the  benefit  of  the 
great  majority  of  readers  who  would  fail  to  recognize  them  from  the 
botanical  description  alone,  are  then  to  be  understood  as  indicating, 
whenever  they  occupy  the  ground  as  an  abundant  and  luxuriant  growth, 
that  such  land  is  irreclaimable  for  ordinary  crops,  unless  underdrained 
for  the  purpose  of  washing  out  surplus  salts.  The  occurrence  merely 
of  scattered,  more  or  less  stunted  individuals  of  these  plants,  while  a 
sure  indication  of  the  presence  of  alkali  salts,  does  not  necessarily  show 
that  the  land  is  irreclaimable. 

The  plants  which  may  best  serve  as  such  indicators  in  California  are 
the  following: 

Tussock-grass  (Sporobolus  airoides,  Torr.),  Fig.  16; 

Greasewood  (Sarcobatus  vermicidatus  (Hook.)   Torr.),  Fig.  17; 

Dwarf  Samphire  (Salicornia  subterminalis,  Parish,  and  other  species), 
Fig.  18; 

Bushy  Samphire  (Allenrolfea  occidentalis  (Wats.)   Ktze.),  Fig.  19; 

Saltwort  (Suaeda  Torreyana,  Wats.,  and  8.  suffrutescens,  Wats.), 
Fig.  20; 

Alkali-heath  (Frankenia  grandifolia  campestris,  Gray),  Fig.  21; 

Cressa  (Cressa  cretica  truxtllensis,  Choisy),  Fig.  22. 


NATURAL  VEGETATION  OF  ALKALI  LAND. 


63 


TUSSOCK-GRASS*    (Sporobolus  airoides,  Torr.)  ;  Fig.  16. 

The  three  sets  of  samples  of  Tussock-grass  soil  which  have  been 
analyzed  show  that  the  total  amount  of  all  salts  present  is  in  no  case 
less  than  49,000  pounds  per 
acre,  to  a  depth  of  four  feet, 
and  that  it  sometimes  reaches 
the  extraordinarily  high  figure 
of  499,000  pounds,  or  more  than 
three  per  cent.  Of  these 
amounts  the  neutral  salts 
(glauber  salt  and  common  salt) 
are  usually  in  the  heaviest  pro- 
portion (glauber  salt,  19,600  to 
323,000  pounds  per  acre;  com- 
mon salt,  3,500  to  172,800)  ;  the 
corrosive  salsoda  varying  from 
3,000  to  44,000  pounds.  Tus- 
sock-grass apparently  can  not 
persist  in  ground  which  is  peri- 
odically flooded.  It  is  of  special 
importance  because  it  is  an 
acceptable  forage  for  stock. 

Tussock-grass  is  a  prevalent 
alkali-indicator  in  the  hot,  arid 
portions  of  the  interior,  from  the 
upper  San  Joaquin  Valley,  the 
Mojave  Desert,  and  southward; 
also  through  southern  Nevada 
and  Utah  as  far  east  as  Kansas 
and  Nebraska.  In  the  San  Joa- 
quin Valley  we  have  not  found 
it  farther  north  than  the  Tulare  plains,  although  east  of  the  Sierra  it 
occurs  near  Reno.  Coville  observes  that  in  the  Death  Valley  region  "it 
is  confined  principally  to  altitudes  below  1,000  meters"  (3,280  feet). 
Hillman,  however,  reports  it  from  near  Reno,  Nevada,  at  an  altitude 
which  can  not  be  much  less  than  4,500  feet. 


FIG.  16.    Tussock-grass— Sporobolus  airoidcs,  Torr. 
(From  Division  of  Agrostology,  U.  S.  Dept.  Agr.) 


GREASE WOODf    (Sarcobatus  vermiculatus    (Hook.),  Torr.)  ;   Fig.   17. 

Through  the  courteous  cooperation  of  Prof.  ¥.  H.  Hillman,  Botanist 
to   the   Nevada  Agricultural   Experiment   Station   at   Reno,   we   have 

*  So-called  because  it  grows  in  large  clumps  or  tussocks,  which  feature  unfor- 
tunately is  not  indicated  in  the  illustration. 

fThis  is  the  true  Greasewood  of  the  desert  region  east  of  the  Sierra  Nevada,  and 
not  either  of  the  plants  known  under  that  name  in  the  San  Joaquin  Valley  and  in 
southern    California. 


64 


UNIVERSITY    OF   CALIFORNIA — EXPERIMENT   STATION. 


obtained  three  series  of  samples  of  Greasewood  soil  from  that  vicinity. 
These  samples  show  that  where  the  Greasewood  shrubs  are  thinly- 
scattered  and  stunted  in  growth,  the  salt  content  per  acre  to  the  depth 
of  three  feet  is  about  2,400  pounds,  of  which  over  one  half  consists  of 
the  corrosive  carbonates.     Where  a  luxuriant  growth  occurs  the  total 


FIG.  17.    Greasewood  (proper)— Sarcobalus  vermiculatus  (Hook.),  Torr. 

A.  Appearance  of  a  branch  when  not  in  blossom. 

B.  Spiny  branchlet  from  the  same. 

C.  Branchlet  bearing  cones  of  male  flowers. 

D.  Cone  of  male  flowers,  enlarged. 

E.  Branch  bearing  fruits. 

F.  Cluster  of  fruits,  enlarged. 

G.  Vertical   section    through  a  fruit,  showing  a  seed   with    its 

curved  embryo  (enlarged;. 


salts  per  acre  vary  from  38,000  to  58,500  pounds,  with  18,700  pounds 
of  salsoda  and  920  to  3,680  pounds  of  common  salt;  the  relative  per- 
centage of  the  injurious  salsoda  is  thus  invariably  high.  The  common 
salt  is  low  and  the  neutral  glauber  salt  is  variable.  This  plant  therefore 
always  indicates  the  presence  of  " black  alkali." 


NATURAL  VEGETATION  OF  ALKALI  LAND. 


65 


Greasewood  is  distinctly  a  plant  of  the  Great  Basin,  only  reaching 
California  in  the  adjacent  counties  of  Lassen,  Alpine,  Mono,  and 
northern  Inyo.  It  is  very  abundant  on  the  lower  levels  of  Honey  Lake 
Valley,  and  evidently  flourishes  best  in  black  alkali. 

DWARF  SAMPHIRE    (Salicornia  subterminalis,  Parish,  and  other  species  of 
the  interior)  ;  Fig.  18. 

The  two  or  three  species  of  Dwarf  Samphire  which  grow  in  the 
interior  valleys  of  the  State  are  nowhere  very  abundant  in  those  por- 
tions of  the  alkali  region 
which  we  have  thus  far 
investigated.  Wherever 
the  species  do  occur, 
however,  they  are  con- 
fined to  such  very 
strongly  saline  soils  that 
they  may  be  considered 
valuable  indicative 
plants.  We  have  as  yet 
only  one  full  set  of 
samples  of  Dwarf  Sam- 
phire soil.  This  shows 
the  total  salt  content  to 
amount  t  o  441,880 
pounds  per  acre  in  a 
depth  of  four  feet.  The 
neutral  glauber  salt 
amounts  to  314,000 
pounds,  almost  as  much 
as  in  Tussock-grass  soil ; 
common  salt  up  to  125,- 
640  pounds,  while  the 
salsoda  varies  from  2,200 
to  12,000.  We  may  con- 
sider this  plant  as  in- 
dicative of  almost  the 
highest  percentage  of  common  salt,  glauber  salt,  and  total  salts.  Like 
the  preceding  species,  it  indicates  " white"  salts  in  excessive  amounts, 
and  a  subsoil  too  wet  for  the  Australian  saltbush. 


FIG.  18.    Dwakk  Samphire—  Salicornia  subterminalis.  Parish. 


BUSHY  SAMPHIRE    (Allenrolfea  occidental**   (Wats.)    Ktze.)  ;  Fig.  19. 

This  plant  is  locally  called  greasewood,  but  as  this  name  is  much  more 
commonly  used  for  Sarcobatus  vermiculatus,  it  seems  best  to  call  Allen- 
rolfea  "bushy  samphire,"  as  it  closely  resembles  the  true  samphire 
(Salicornia) . 

5— bul.  128-133 


66 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION. 


Bushy  samphire  usually  grows  in  low  sinks,  in  soil  which  in  winter 
is  excessively  wet  and  in  summer  becomes  a  ' '  dry  bog. ' '    Wherever  the 


FIG.  19.    Bushy  Samphire— Allenrolfea  occidental™  (Wats.)  Ktze. 
[Called  "Grcasewood  "  in  San  Joaquin  Valley.] 

plant  grows  luxuriantly  the  salt  content  is  invariably  high,  the  total 
salts  varying  from  327,000  pounds  per  acre  to  a  depth  of  three  feet,  to 
494,520  pounds  in  four  feet.     The  salts  consist  mainly  of  glauber  and 


NATURAL  VEGETATION  OF  ALKALI  LAND. 


67 


common  salts  (a  maximum  of  about  275,000  pounds  of  each)  ;  salsoda 
varies  from  2,360  to  4,800  pounds  per  acre.  The  percentage  of  common 
salt  and  total  salts  is  higher  than  for  any  other  plant  investigated,  and 
the  glauber  salt  is  almost  proportionate.  The  areas  over  which  this 
plant  grows  must  therefore  be  considered  as  among  the  most  hopeless 
of  alkali  lands,  for  although  its  salts  are  "white,"  submergence  during 
winter  precludes  the  growth  of  Australian  saltbush. 

Bushy  samphire  is 
a  common  plant  in 
alkali  soils  in  the 
upper  San  Joaquin 
Valley,  around  Bak- 
ersfield  and  Delano ; 
a  few  stunted  bushes 
occur  near  the  margin 
of  Tulare  Lake,  west 
of  Tulare,  but  at  that 
point  it  appears  to  be 
dying  out.  It  also 
occurs  on  the  east 
slope  of  Livermore 
Pass,  and  in  an  alkali 
sink  in  a  pocket  of 
the  hills  at  Byron 
Springs,  Contra 
Costa  County.  In 
the  Death  Valley  re- 
gion the  plant  appears 
to  be  .very  abundant, 
occupying  an  area 
considerably  more 
southern  than  what  appears  to  be  the  southerly  limit  of  Greasewood 
(Sarcobatus) . 


FIG.  20.    Saltwort — Suaeda  Torreyana,  Wats. 


SALTWORT   (Suaeda  Torreyana,  Wats.,  8.  suffrutescens,  Wats, 
one  other  species)  ;   Fig.  20. 


and  perhaps 


Samples  of  Saltwort  soil  from  Bakersfield,  Kern  County,  and  Byron 
Springs,  Contra  Costa  County,  taken  to  a  depth  of  one  foot  and  three 
feet  respectively,  show  that  this  plant  grows  luxuriantly  in  a  soil  con- 
taining 130,000  pounds  of  salts  per  acre  in  the  first  foot,  and  with 
10,480  pounds  of  the  noxious  salsoda  and  39,760  pounds  of  common 
salt  in  three  feet ;  while  only  a  sparse  growth  is  found  on  soils  contain- 
ing only  3,700  pounds  of  salts  in  three  feet.  It  thus  appears  to  indicate 
a  lower  percentage  of  salsoda  than  does  Greasewood,  but  a  higher  per- 


68 


UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION. 


centage  than  Bushy  Samphire.  Further  investigation  is  necessary  to 
determine  the  exact  relation  of  the  different  salts  to  the  growth  of  the 
plant,  and  as  to  whether  carbonates  always  occur  in  large  quantity; 
but  enough  data  have  been  gathered  to  show  that  a  luxuriant  growth 
of  saltwort  indicates  a  soil  practically  irreclaimable  except  at  the 
expense  of  leaching. 


ALKALI-HEATH   (Frankenia  gr an di folia  campestris,  Gray)  ;  Fig.  21. 

Alkali-heath  is  perhaps  the  most  widely  distributed  of  any  of  our 
California  alkali  plants.    Its  perennial,  deep-rooting  habit  of  growth, 

and  flexible,  somewhat 
wiry  rootstock,  which  en- 
ables it  to  persist  even  in 
cultivated  ground,  render 
it  a  valuable  plant  as  an 
alkali  indicator.  The  salt 
content  where  Alkali-heath 
grows  luxuriantly  is  inva- 
riably high,  ranging  from 
64,000  to  282,000  pounds 
per  acre;  salsoda  varies 
from  680  to  19,590  pounds ; 
common  salt  ranges  from 
5,000  to  10,000  pounds. 
Such  soils  would  not  be 
benefited  by  the  applica- 
tion of  gypsum,  as  the 
salts  are  already  largely 
in  the  neutral  state.  Of 
useful  plants  only  Saltbushes  and  Tussock-grass  are  likely  to  flourish 
in  such  lands. 

While  Alkali-heath  is  thus  one  of  the  most  alkali-tolerant  plants,  it 
is  at  the  same  time  capable  of  growth  with  a  minimum  of  salts  (total 
salts  3,700  pounds,  salsoda  680  pounds).  Where  only  a  sparse  growth 
of  this  plant  occurs,  therefore,  the  land  should  not  be  condemned  until 
a  chemical  examination  of  the  soil  has  been  made. 

Alkali-heath  is  found  on  soils  of  very  varying  physical  texture  and 
degrees  of  moisture;  while  on  soils  of  uniform  texture  and  moisture, 
but  differing  in  chemical  composition,  it  varies  with  the  varying  salt- 
content. 

It  has  been  found  that  Australian  Saltbush  (Atriplex  semibaccata) 
can  be  successfully  grown  on  the  Colusa  County  "goose  lands,"  on  soil 
producing  a  medium  crop  of  Alkali-heath;   it  remains  to  be  shown 


FIG.  21.    Alkali-heath— Frankenia    grandifolia 
campesttis,  A.  Gray.     • 


RELATIVE  TOLERANCE  OF  NATIVE  ALKALI  PLANTS. 


69 


whether  it  will  do  equally  well  on  soils  producing  a  dense  and  luxuriant 
growth  of  the  same. 

Alkali-heath  is  widely  distributed  throughout  the  interior  valleys  of 
California.  A  closely  related  form  is  found  in  salt  marshes  along  the 
coast,  differing  from  that  of  the  interior  principally  in  its  much  broader 
Jeaves. 


CRESSA    (Gressa  cretica  truxillensis,  Choisy)  ;  Fig.  22. 

Cressa  soils  show  a  low  percentage  of  the  noxious  salsoda,  but  com- 
paratively heavy  total  salts 
(161,000  to  282,000  pounds 
per  acre).  Common  salt 
varies  from  5,760  to  20,840 
pounds  per  acre  in  four  feet. 
The  maximum  is  lower  than 
in  the  case  of  Alkali-heath, 
but  Cressa  seems  to  be  much 
more  closely  restricted  to 
strong  alkali  than  does  the 
former  species.  Cressa  ap- 
pears to  be  as  widely  dis- 
tributed through  the  interior 
valleys  of  the  State  as  Alkali- 
heath.  It  is  a  cosmopolitan 
plant,  occurring,  as  its  name 
indicates,  on  the  Ionian  Isles, 
as  well  as  in  North  Africa, 
Syria,  and  in  other  arid 
countries  of  the  world. 


FIG.  22.    Cressa—  Cressa  cretica  truxillensis,  Choisy. 


RELATIVE    TOLERANCE    OF    THE    DIFFERENT    SPECIES. 

In  order  to  determine  the  relative  nature  of  the  soils  characterized 
by  each  of  the  above-named  plants,  Mr.  Davy  has  prepared  the  follow- 
ing table,  in  which  the  column  marked  optimum  shows,  as  nearly  as 
possible  with  our  present  knowledge  of  the  subject,  the  condition  of  the 
soil  where  each  species  grows  in  about  equal  luxuriance.  For  Saltwort 
and  Dwarf  Samphire  we  have  not  yet  been  able  to  obtain  as  thoroughly 
characteristic  soil  samples  as  could  be  desired,  but  we  hope  to  be  able  to 
do  so  during  the  coming  season. 

It  must  be  understood  that  the  optimum  indicates  the  condition  under 
which  the  plant  has  been  found  at  its  greatest  luxuriance— where  it  is 
evidently  "at  home"—;  whereas  the  maximum  and  minimum  have 
sometimes  been  obtained  where  the  plants  were  more  or  less  stunted  in 
growth  and  sparingly  scattered  over  the  ground. 


70 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION. 


Table  Showing  Optimum,  Maximum,  and  Minimum  of  Salts  Tolerated  by  Each  of  the 

Several  Alkali  Plants. 


Total  Salts. 


Bushy  Samphire  . 
Dwarf  Samphires 

Alkali-heath 

Cressa  

Saltworts 

Grease  wood 

Tussock-grass 


Carbonates  (Salsoda). 


Tussock-grass 

Alkali-heath 

Grease  wood 

Dwarf  Samphires 

Saltworts  ___ 

Cressa 

Bushy  Samphire  . 


Chlorids  (Common  Salt). 

Bushy  Samphire .. 

Dwarf  Samphires 

Saltworts 

Cressa  


Alkali-heath  . 

Tussock-grass 
Greasewood  .. 


Sulfates  (Glauber  salt). 

Dwarf  Samphires 

Bushy  Samphire 

Cressa - 


Alkali-heath  . 

Saltworts 

Greasewood  .. 
Tussock-grass 


Pounds  per  Acre. 


Optimum. 


494,520 

441,880 

281,960) 

64,300f 

281,960 

130,000 

58,560 

49,000 


23,000 

*19,590( 

680J 

18,720 

12,120 

10,480 

5,440 

4,800 


212,080 

125,640 

39,760 

20,840 

10,180) 

5,760( 

6,200 

3,680 


314,040 

277,640 

275,520 

275,520) 

34,530f 

44,160 

36,160 

19,640 


Maximum. 


494,520 

441,880 

499,040 

281,960 

153,020 

58,560 

499,040 


44,460 

19,590 

18,720 

12,120 

12,120 

5,440 

4,800 


275,160 

125,640 

52,900 

20,840 

212,080 

172,800 
3,680 


314,040 
277,640 
275,520 

323,200 

104,040 

36,160 

323,200 


Minimum. 


135,060 
441,880 

3,720 

161,160 

3,720 

2,400 

49,000 


3,040 

680 

1,280 
2,200 
1,120 
680 
1,500 


56,800 

125,640 

1,040 

5,760 

1,040 

3,530 
160 


314,040 

50,080 

134,880 

1,560 

1,560 

960 

19,640 


*This  plant  grows  with  equal  luxuriance  in  soils  containing  only  680  pounds  of  carbonates. 

In  these  tables  the  sequence  of  the  different  plants  has  been  arranged 
so  that  in  each  case  the  species  having  the  highest  optimum  comes  at 
the  head  of  the  list.  Arranged  in  this  way  the  tables  show  that  where 
these  plants  grow  in  luxuriance  they  may  be  considered  indicative  of 
the  following  conditions: 

Total  Salts  Indicators.— The  Samphires,  Alkali- heath,  and  Cressa  are 
all  indicative  of  excessive  total  salts.  Saltwort,  Greasewood,  and 
Tussock-grass  indicate  much  lower  total  salt-content;  indeed,  the  maxi- 
mum of  the  two  latter  plants  (Greasewood  and  Tussock-grass)  is  so  low 
that  the  application  of  gypsum  (land-plaster)  would  in  some  cases 
(e.  g.  the  Tussock-grass  lands  near  Bakersfield)  render  the  soil  adapted 
to  the  cultivation  of  Modiola  and  Australian  Saltbush. 


TOLERANCE  OF  ALKALI :     CONCLUSIONS.  71 

Salsoda  Indicators.— It  is  noticeable  that  the  relative  position  of  the 
different  species  in  the  columns  of  optimum  and  maximum  is  more 
uniform  in  the  salsoda  table  than  in  any  other ;  and  whether  we  arrange 
the  sequence  of  the  plants  according  to  the  optimum  or  to  the  maximum, 
the  same  relative  position  is  maintained.  This  is  in  complete  accord 
with  what  our  knowledge  of  the  effect  of  salsoda  on  vegetable  life 
would  lead  us  to  expect ;  being  by  far  the  most  injurious  of  the  alkali 
salts,  the  range  of  tolerance  is  much  smaller,  and  the  limits  are  much 
more  clearly  denned  than  in  the  case  of  the  other  salts. 

Luxuriant  growths  of  Tussock-grass  and  Greasewood  are  invariably 
indicative  of  high  percentages  of  carbonates,  but  in  such  cases  the  total 
salt  percentage  is  sometimes  so  low  that  the  application  of  gypsum  (land- 
plaster)  would  render  the  land  fit  for  the  cultivation  of  Modiola  or 
even  Australian  Saltbush,  as  noted  above.  It  must  be  borne  in  mind, 
however,  that  where  Tussock-grass  grows  but  sparsely,  the  total  salt- 
content  may  reach  499,000  pounds,  an  amount  rendering  the  land  utterly 
worthless  for  agricultural  purposes  unless  the  surplus  salts  can  be 
removed. 

Alkali-heath  can  not  be  taken  as  an  accurate  gauge  of  the  salsoda 
content,  as  it  grows  with  equal  luxuriance  on  soils  containing  respec- 
tively 680  and  19,590  pounds  to  the  acre,  of  this  salt. 

The  Samphires  and  Saltworts  are  relatively  low  down  in  the  carbonate 
table,  and  may  be  taken  to  indicate  a  comparatively  low  percentage  of 
" black  alkali." 

Neutral-Salt  Indicators.— The  Samphires  and  Saltworts  head  the 
neutral-salt  tables,  and  are  reliable  indicators  of  excessively  high  per- 
centages both  of  glauber  salt  and  of  common  salt.  Saltwort  comes 
next  to  Samphire  in  the  common-salt  table,  but  is  not  quite  such  a 
good  guide  to  the  glauber  salt. 

Luxuriant  growths  of  Alkali-heath,  Greasewood,  and  Tussock-grass 
indicate  low  percentages  of  the  neutral  salts,  but  these  plants  will  some- 
times tolerate  (in  a  sparse  state  of  growth)  very  high  percentages. 


CONCLUSIONS. 

A  review  of  the  above  tables  and  of  the  more  detailed  results  brings 
with  it  the  following  conclusions : 

1.  While  for  the  crops  in  general  the  maximum  tolerance  for  alkali 
salts  has  not  yet  been  definitely  found,  close  approximations  are  reached 
with  a  number,  such  as  the  apple,  peach,  orange,  and  lemon  trees,  with 
respect  to  carbonate  of  soda  and  common  salt.  In  one  or  two  instances 
alone  was  the  sulfate  of  soda  the  apparent  cause  of  distress  on  the  part 
of  a  tree. 


72  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION. 

2.  Grapes  and  olives  thus  far  stand  at  the  head  among  fruits  in  their 
tolerance  of  each  of  the  alkali  salts ;  oranges  grew  in  a  larger  amount  of 
carbonate  than  did  the  olive,  but  that  salt  was  chiefly  held  below  the  two 
surface  feet.  On  the  other  hand,  the  lemon  seems  to  be  the  most  sensi- 
tive to  the  effects  of  alkali,  especially  to  common  salt,  and  next  to  it 
the  orange. 

3.  The  amount  tolerated  depends  largely  upon  the  distribution  of 
the  several  salts  in  the  vertical  soil-column,  the  injury  being  most 
severe  in  the  surface  foot,  where  under  the  influence  of  the  unfortunate 
practice  of  surface-irrigation  the  feeding  rootlets  are  usually  found. 
It  is  therefore  important  that  in  alkali  regions  such  methods  of  culture 
and  irrigation  should  be  followed  as  to  encourage  deep  rooting  on  the 
part  of  crops. 

4.  The  amount  tolerated  varies  with  the  variety  of  the  same  plant,  as 
shown  in  the  grape. 

5.  The  amount  of  alkali  tolerated  by  the  various  cultures  varies  with 
the  nature  of  the  soil.  It  is  lowest  in  heavy  clay  soils  and  fine-grained 
soils,  in  which  the  downward  movement  of  plant  roots  is  restricted; 
and  highest  in  loam  and  sandy  soils,  in  which  the  roots  have  freedom 
of  penetration. 

6.  Some  plants,  such  as  the  saltbush  and  alfalfa,  are  quite  susceptible 
to  alkali  salts  when  young,  but  when  the  roots  penetrate  deeply,  and 
the  ground  is  heavily  covered  with  the  foliage  of  the  plant,  they  are 
immune  to  a  very  large  extent. 

7.  Lands  heavily  charged  with  alkali  may  often  be  made  productive 
for  certain  crops  by  the  application  of  irrigation  water  in  sufficient 
amount  to  leach  the  salts  down  to  a  depth  of  several  (five  or  six)  feet, 
and  by  preventing  their  subsequent  rise  by  proper  mulching,  or  cultiva- 
tion until  the  foliage  of  the  plant  itself  will  prevent  evaporation  of  the 
soil  moisture  from  the  surface  of  the  ground.  Alfalfa  culture  has  thus 
been  made  highly  profitable  in  lands  once  so  strongly  charged  with 
alkali  as  to  kill  all  vegetation. 

8.  The  reclamation  of  lands  charged  with  carbonate  of  soda  by 
neutralization  with  gypsum  often  renders  possible  the  profitable  plant- 
ing of  such  crops  as  withstand  large  amounts  of  common  salt  or  of 
glauber  salt. 

9.  The  effects  of  carbonate  of  soda  are  seen  in  the  yellowing  of  the 
leaves  of  the  tree  caused  by  its  corrosive  action  on  the  root-crown, 
whereby  the  proper  flow  of  sap  and  food  supply  to  the  leaves  is  pre- 
vented. The  effect  of  common  salt  is  seen  in  the  falling  of  the  leaves 
from  the  newer  branches,  and  in  the  blackening  and  curling  of  the 
leaves  of  pears. 


TOLERANCE   OF  ALKALI  :     CONCLUSIONS.  73 

10.  Sulfate  of  soda  (glauber  salt)  is  hurtful  only  when  present  in 
very  large  amounts,  most  cultures  doing  well  in  more  than  10,000 
pounds  per  acre  in  four  feet  depth;  saltbush,  hairy  vetch,  alfalfa,  and 
sorghum  grew  well  in  more  than  61,000  pounds. 

11.  Barley  is  better  adapted  to  alkali  land  than  is  wheat,  for  it  will 
withstand  the  effects  of  twice  the  amount  of  carbonate  of  soda  and  com- 
mon salt.  Of  course,  the  carbonate  may  be  neutralized  with  gypsum, 
and  in  the  absence  of  much  common  salt  will  permit  of  the  growth  of 
excellent  crops  of  wheat ;  but  where  the  amount  of  common  salt  exceeds 
5,000  pounds  barley  should  be  given  the  preference  over  wheat. 


6— bul.  128-133 


CALIFORNIA  PUBLICATIONS  AVAILABLE  FOR  DISTRIBUTION. 


REPORTS. 


1896.  Report   of    the   Viticultural    Work    during    the   seasons    1887-93,    with    data 

regarding  the  Vintages  of  1894-95. 

1897.  Resistant   Vines,   their    Selection,   Adaptation,    and    Grafting.      Appendix    to 

Viticultural  Report  for  1896. 

1898.  Partial  Report  of  Work  of  Agricultural  Experiment  Station  for  the  years 

1895-96  and  1896-97. 
1900.     Report  of  the  Agricultural  Experiment  Station  for  the  year  1897-98. 

1902.  Report  of  the  Agricultural  Experiment  Station  for  1898-1901. 

1903.  Report  of  the  Agricultural  Experiment  Station  for  1901-1903. 

1904.  Twenty-second  Report  of  the  Agricultural  Experiment  Station  for  1903-1904. 

BULLETINS. 

Reprint.  Endurance  of  Drought  in  Soils  of  the  Arid  Region. 

No.  131.  The  Phylloxera  of  the  Vine. 

133.  Tolerance  of  Alkali  by  Various  Cultures. 

135.  The  Potato-Worm  in  California. 

137.  Pickling  Ripe  and  Green  Olives. 

138.  Citrus  Fruit  Culture. 

139.  Orange  and  Lemon  Rot. 

140.  Lands  of  the  Colorado  Delta  in  Sal  ton  Basin,  and  Supplement. 

141.  Deciduous  Fruits  at  Paso  Robles. 

142.  Grasshoppers  in  California. 

143.  California  Peach-Tree  Borer. 

144.  The  Peach- Worm. 

145.  The  Red  Spider  of  Citrus  Trees. 

146.  New  Methods  of  Grafting  and  Budding  Vines. 

147.  Culture  Work  of  the  Substations. 

148.  Resistant  Vines  and  their  Hybrids. 

149.  California  Sugar  Industry. 

150.  The  Value  of  Oak  Leaves  for  Forage. 

151.  Arsenical  Insecticides. 

152.  Fumigation  Dosage. 

153.  Spraying  with  Distillates. 

154.  Sulfur  Sprays  for  Red  Spider. 

155.  Directions  for  Spraying  for  the  Codling-Moth. 

156.  Fowl  Cholera. 

157.  Commercial  Fertilizers. 

158.  California  Olive  Oil ;   its  Manufacture. 

159.  Contribution  to  the  Study  of  Fermentation. 

160.  The  Hop  Aphis. 

161.  Tuberculosis  in  Fowls. 

162.  Commercial  Fertilizers.     (Dec.  1,  1904.) 

163.  Pear  Scab. 

164.  Poultry  Feeding  and  Proprietary  Foods. 

165.  Asparagus  and  Asparagus  Rust  in  California. 

166.  Spraying  for  Scale  Insects. 

167.  Manufacture  of  Dry  Wines  in  Hot  Countries. 

168.  Observations  on  Some  Vine  Diseases  in  Sonoma  County. 

169.  Tolerance  of  the  Sugar  Beet  for  Alkali. 

170.  Studies  in  Grasshopper  Control. 

171.  Commercial  Fertilizers.      (June  30,  1905.) 

CIRCULARS. 

No.  1.  Texas  Fever.  No.  12.     Silk  Culture. 

2.  Blackleg.  13.     The  Culture  of  the  Sugar  Beet. 

3.  Hog  Cholera.  14.     Practical    Suggestions   for   Cod- 

4.  Anthrax.  ling-Moth      Control      in      the 

5.  Contagious  Abortion  in  Cows.  Pajaro  Valley. 

7.     Remedies  for  Insects.  15.     Recent  Problems  in  Agriculture. 

9.     Asparagus  Rust.  What   a    University    Farm    is 

10.  Reading    Course    in    Economic  For. 

Entomology.  16.     Notes  on  Seed- Wheat. 

11.  Fumigation  Practice. 

Copies  may  be  had  by  application  to  the  Director  of  the  Experiment 
Station,  Berkeley,  California. 


